The formula is as follows: The proof is very similar to the … This is the equation to find the slope (m): m - rise/run (y2-y1)/(x2-x1) Example: points … What is the slope (or gradient) of this line? Now I want to find the linear equation of a line passing through these 2 points. This video explains how to find the equation of a line when given 2 points. Finding the Equation of a Line Given Two Points : Here we are going to see some example problems on determining the equation of the line from two points. The second way is to use two points from one line and one point from a perpendicular line. The equation of a straight line is satisfied by the co-ordinates of every point lying on the straight line and not by any other point outside the straight line. There are 3 steps to find the Equation of the Straight Line : What is the slope (or gradient) of this line? Slope = y 2 − y 1 x 2 − x 1. Finding the equation of the line given its graph If you are given the graph of a line and want to find its equation, then you first find the slope as in Example \(\PageIndex{1}\). Work out the equation of the line, giving your answer in the form + + = 0. Substitute the slope for 'm' in the slope intercept form of the equation. There are a few different ways to find the equation of line from 2 points. y = 2x +b, Substitute either point into the equation. If you know two points that a line passes through, this page will show you how to find the equation of the line. Equation of a Line: Standard Form - Level 2 Use the given two points, (x 1, y 1) and (x 2, y 2) to find the slope and apply point-slope formula to write the equation of a line.Express the equation in standard form. Real World Math Horror Stories from Real encounters. Hello, I have two points (x1,y1) and (x2,y2). The equation of a line is typically written as y=mx+b where m is the slope and b is the y-intercept.. Position vectors simply denote the position or location of a point in the three-dimensional Cartesian system … Substitute the slope for 'm' in the point slope equation, y − y1 = m(x −x1) y − y1 = ½(x −x1), using (4,5): Help make finding the equation of a line given two points much easier for your students with this math resource. Students learn to write the equation of a line given two points on the line, by first finding the slope of the line using the slope formula, m = (y2 – y1)/(x2 – x1), then substituting the slope and one of the given points into the point-slope formula, y – y1 = m(x – x1). By using this website, you agree to our Cookie Policy. Step 2. In this case, since only two points were given, the y-intercept of the line is not readily known. ), Find the equation of a line through the following 2 points: (4,5) and (8,7), y = mx +b Just type numbers into the boxes below and the calculator (which has its own page here) will automatically calculate the equation of line in point slope and slope intercept forms, ( Try this 'equation from 2 points' calculator on its own page here . Which is now in the Slope-Intercept (y = mx + b) form. Then you use one of the points you found \(\left(x_1,\:y_1\right)\) when you computed the slope, \(m\), and put it into the point slope equation : To find the slope of the line passing through these two points we need to use the slope Revise how to work out the equation of a straight line can be worked out using coordinates and the gradient, and vice versa as part of National 5 Maths. Given Two Points 1. After you finish this lesson, view all of our Algebra 1 lessons and practice problems. 6−2 You can use either (3,7) or (5,11), using (3,7): You can use either (-6,7) or (-9,8), Substitute b, 5, into the equation from step 2, $$ I'm aware of how straight lines on a log-log plot are described by monomials, but I'm not sure exactly how to work backwards to that monomial given two points on the line. Access it free on Front Porch Math. The equation of a line is such that its highest exponent on its variable(s) is 1. $$, Find the equation of a line through the following the 2 points: (-3,6) and (15,-6), Substitute either point into the equation. Step 2: Use the slope to find the y-intercept. And you don't have to draw it to do this problem but it always help to visualize That is my y axis. Video Transcript A line passes through points three, three and negative one, zero. Find the Equation of a Line Given That You Know Two Points it Passes Through The equation of a line is typically written as y=mx+b where m is the slope and b is the y-intercept. Finding the equation of the line given its graph If you are given the graph of a line and want to find its equation, then you first find the slope as in Example \(\PageIndex{1}\). Write the Equation of the Line:Given two points Write the slope-intercept form of the equation of the line through the given points. Instead of 5 steps, you can find the line's equation in 3 steps, 2 of which are very easy and require nothing more than substitution! a) b) a) c) 3. Therefore, Helena is correct since we cannot find out the intercept c and hence Samuel's method is incorrect, Hope this answer is helpful. Find an equation for each line. We know two points: point "A" is (6,4) (at x is 6, y is 4) Write Equations Of A Line When Given Two Points - Displaying top 8 worksheets found for this concept. Explanations follow. Finding the Equation of a Line Given Two Points 2 - Cool Math has free online cool math lessons, cool math games and fun math activities. Question 396179: Given two points on the line, input the equation of the line in standard form Ax + By = C. Reduce all fractional answers to lowest terms. How it works: Just type numbers into the boxes below and the calculator will automatically calculate the equation of line in standard, point slope and slope intercept forms. Writing Linear Equations Given Two Points For FREE access to this lesson, select your course from the categories below. change in x As explained at the top, point slope form is the easier way to go. Similarly, in three-dimensional space, we can obtain the equation of a line if we know a point that the line passes through as well as the direction vector, which designates the direction of the line. In fact, the only calculation, that you're going to make is for the slope. Equation of a line from two points. This is done step by step using a table. Put the slope and one point into the "Point-Slope Formula" 3. y = m x +b. Then you use one of the points you found \(\left(x_1,\:y_1\right)\) when you computed the slope, \(m\), and put it into the point slope equation : y = \frac{1}{3}x +\red{5} y − 11 = 2(x − 5), y − y1 = m(x −x1) This online calculator finds equation of a line in parametrical and symmetrical forms given coordinates of two points on the line person_outline Timur schedule 2019-06-07 06:42:44 You can use this calculator to solve the problems where you need to find the equation of the line that passes through the two points with given coordinates. Here are two points (you can drag them) and the equation of the line through them. Free line equation calculator - find the equation of a line step-by-step This website uses cookies to ensure you get the best experience. In this video we find the standard form equation of a line given two points on that line. change in y Finding the Equation of a Line Given Two Points 1 - Cool Math has free online cool math lessons, cool math games and fun math activities. Equation of a line is defined as y= mx+c, where c is the y-intercept and m is the slope. −1 However, if you are comfortable using the point slope form of a line, then skip to the second part of this page because writing the equation from 2 points is easier with point slope form . y − y1 = 2(x −x1), Substitute either point as x1, y1 in the equation. Find the equation of a line through the points (3,7) and (5,11), Substitute the slope for 'm' in the slope intercept form of the equation, y = mx +b The first half of this page will focus on writing the equation in slope intercept form like example 1 below. = 0.25. This kind of conversion is very useful in many geometric algorithms like intersection of lines, finding the circumcenter of a triangle, finding the incenter of a triangle and many more… Examples: Equation of a Line passing through two given points Let us consider that the position vector of the two given points A and B be \(\vec{a} \) and \(\vec{b} \) with respect to the origin. Free. change in y 4.1 8 customer reviews. The equation of a straight line is satisfied by the co-ordinates of every point lying on the straight line and not by any other point outside the straight line. Vectors can be defined as a quantity possessing both direction and magnitude. You can use either (4,5) or (8,7), Substitute b, 3, into the equation from step 2, Find the equation of a line through the following the points: (-6,7) and (-9,8), Substitute the slope for 'm' in the slope intercept equation, Substitute either point into the equation. Finding the Equation of a Line Given Two Points – Practice Problems Page 2 of 4 Detailed Solutions 1. It doesn't matter which point comes first, it still works out the same. Start with the "point-slope" formula (x1 and y1 are the coordinates of a point on the line): We can choose any point on the line for x1 and y1, so let's just use point (2,3): That is an answer, but we can simplify it further. To find the equation of a line in a two-dimensional plane, we need to know a point that the line passes through as well as the slope. Really clear math lessons (pre-algebra, algebra, precalculus), cool math games, online Learn how to write the equation of a line given two points on the line. (7, -3), (4, -8) I keep getting stuc Program to find the equation of a line given two end points Enter X1: 2 Enter Y1: 3 Enter X2: 5 Enter Y2: 7 Equation of the line with end points (2, 3 and (5, 7) : Y = 1.33333X +0.333333 Press any key to continue . y = 2x +b. Find the slope using the slope formula, . When two points (x1, x2), (y1, y2) are given and the equation contains these two points, the first step is to find the slope of the line. Equation of a Line: Standard Form - Level 2 Use the given two points, (x 1, y 1) and (x 2, y 2) to find the slope and apply point-slope formula to write the equation of a line. = 0.25, Now put that slope and one point into the "Point-Slope Formula". on a graph by how far along and how far up it is: Example: The point (12,5) is 12 units along, and 5 units up. Samuel claims that slope-intercept form will generate the equation and Helena claims that - 16588419 . Enter any Number into this free calculator. Step 1: Find the slope of the line. Finding Equation of a Line From Two Points Worksheet : Here we are going to see some practice problems on finding equation of the line from given points. Writing Algebra Equations Finding the Equation of a Line Given Two Points We have written the equation of a line in slope intercept form and standard form. This calculator finds the distance between two given points A (xA , yA) and B (xB , yB), the slope and the equation of a line trough the two points. Express the equation in standard form. Free Algebra Solver ... type anything in there! But there is still a way of writing the equation: use x= instead of y=, like this: 2. y − 11 = ½(x − 5), If a line goes through the following 2 points, what is the line's equation? Try swapping the points: m  =   The equation of a line given two points needs to be found. If you a point that a line passes through, and its slope, this page will show you how to find the equation of the line. Write the Equation of a Line Through Two Points Part I. y − y1 = (x −x1), using (-6,7): A9c – Finding the equation of a line through two given points or through one point with a given gradient This is the students’ version of the page. Find the slope of the line that passes through each pair of points. Help make finding the equation of a line given two points much easier for your students with this math resource. This video explains how to find the equation of a line when given 2 points. a point y = \frac{1}{3}x +\red{b} Step 3. Formulas for Distance, Slope and Equation Given two Points This calculator uses the It also outputs direction vector and displays line and direction vector on a graph. Step 1: Find the slope of the line. Second calculator finds the line equation in parametric form, that is, . Write the Equation of the Line:Given two points Write the slope-intercept form of the equation of the line through the given points. The main advantage, in this case, is that you do not have to solve for 'b' like you do with slope intercept from. What is the equation of the line? Given two points P and Q in the coordinate plane, find the equation of the line passing through both the points. Finding the Equation of a Line Given Two Points – Notes Page 3 of 4 Example 3: Find the equation of the line passing through the points (–5, –2) and (1, 5). This is a chord of the circle. Calculate the slope from 2 points. Given any two points on a line, you can calculate the slope of the line by using this formula: Example: Given two points, P = (0, –1) and Q = (4,1), on the line, find the equation of the line. The first way is to solve for the equation of a line with one (,) point and the equation of a line that runs perpendicular to it. The equation of a line through two points The straight line through two points will have an equation in the form \ (y = mx + c\). 1) through: (−2, −2) and (2, −5) 2−6 Equation of Line from 2 Points Calculator. So that is my x axis. Equation of a line Two Point Form Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. y − 8 = (x +9), Substitute either point into the equation -3,6) and (15,-6), using (-3, 6): We use Cartesian Coordinates to mark change in x We have also written the equation of a line when given slope and a point. This is because it only requires the substitution of the x and y-coordinates of the points in the equation. y + 6 = (x − 15 ), If you read this whole page and looked at both methods (slope intercept form and point slope, you can see that it's substantially quicker to find the equation of line through 2 points by means of point slope. 4−3 m is the slope of the line. Step by step explanation is provided. a) A(2, 3) and B(4, 5) b) M(0, 6) and N(2, 0) c) S(8, 7) and T(0, 0) d) C(3, 4) and D(6, 7) e) P(5, 1) and Q(4, 5) f) E(2, 3) and F(4, 5) g) V(–1, 1) and W(2, –4) h) J(2, –1) and K(1, –2) 2. Access it free on Front Porch Math. The Corbettmaths video tutorial on finding the equation of a line passing through two points The equation of a straight line is satisfied by the co-ordinates of every point lying on the straight line and not by any other point outside the straight line. (Using y = mx+b, substitute x, y, and the slope (m) and solve the equation for b.) Find the slope of the line; 2. 4 y − 7 = 2(x− 3), using (5,11): Now I want to find the linear equation of a line passing through these 2 points. Steps For Writing Equations Given Two Points Use the slope formula to find the slope. Log in above for the teachers’ version. Hint: Find the equation of the line passing through the two given points. After finding the slope, plug in the value of your points into either slope-intercept form, or point-slope form, to get the equation of the line. It also outputs slope and intercept parameters and displays line on a graph. y − 6 = (x + 3), using (15, -6): If we have any two points on the line, we can use this formula to find the equation. SOLUTION: Given two points on the line, input the equation of the line in standard form Ax + By = C. Reduce all fractional answers to lowest terms. b is the y-intercept. This online calculator can find and plot equation of a straight line passing through the two given points. … on Finding the Equation of a line From 2 points. year 8eqn from 2 points About this resource Info Created: Dec 28, 2011 Updated: Jan 20, 2015 doc, 71 KB year 8eqn from 2 points Report a problem This resource is designed for UK teachers. Finding the Equation of a Line Given Two Points Most people when asked, “What is the equation of a line?”, will answer, “y = mx + b”. (-6,7) and (-9,8), y − y1 = m(x −x1) Created: Dec 28, 2011 | Updated: Jan 20, 2015. Is there any function in matlab that accepts coordinates of two points an gives the related linear equation back?   =   Find the slope using the slope formula, . To find the equation of a line using 2 points, start by finding the slope of the line by plugging the 2 sets of coordinates into the formula for slope. Slope m  =  change in ychange in x  =  yA − yBxA − xB, m  =   Let us confirm by testing with the second point (6,4): y = x/4 + 5/2 = 6/4 + 2.5 = 1.5 + 2.5 = 4. The coordinates in this Really clear math lessons (pre-algebra, algebra, precalculus), cool math games, online graphing calculators, geometry art, … Math example the equation of a line given two points 27 media4math how to find 2 wonderhowto learning algebra can be easy learn you writing equations standard form with tessshlo linear using slope intercept 1 formulating mathplanet 8 steps pictures Math Example The Equation Of A Line Given Two Points 27 Media4math How To Find The Equation Of… Read More » Simplify to Slope-Intercept (y = mx + b) form: The previous method works nicely except for one particular case: a vertical line: A vertical line's gradient is undefined (because we cannot divide by 0): m = yA − yBxA − xB = 4 − 12 − 2 = 30 = undefined. Let us choose any random point R on the line and its position vector with respect to origin of the rectangular co-ordinate system is given by \(\vec{r} \). These online calculators find the equation of a line from 2 points. The Equation of a Line Calculator is an online tool that shows the slope and equation of a line, for the given input. Thus, it is only through the point-slope form that the equation of the line can be determined. 3−4 The equation must be like f(x)=a*x+b.   =   Hello, I have two points (x1,y1) and (x2,y2). Given two discrete points on a log-log plot and a defined minimum value on both axes, how would you determine the equation of the line that runs through both points? BYJU’S two-point form calculator makes it simple to find the slope of a line if the coordinates of the two points are given. Finding the Equation of a Line Given Two Points – Notes Page 2 of 4 Step 3: Write the answer. First calculator finds the line equation in slope-intercept form, that is, . If you continue browsing the site, you agree to the use of cookies on this website. Interactive simulation the most controversial math riddle ever! A line goes through the points (-1, 6) and (5, 4). Given two points A(x1, y1, z1) and B(x2, y2, z2) and a set of points (a, b, c) which represent the axis (ai + bj + ck), the task is to find the equation of plane which passes through the given points A and B and parallel to the given axis. Practice Problems with challenge problems Part III. Author: Created by Tristanjones. Finding the Equation of a Line Given Two Points : Here we are going to see some example problems on determining the equation of the line from two points. \\ You can use either (-3,6) or (15,-6). Therefore, we can find out the equation of the line using point-slope form. Find the equation of a line through the points (3,7) and (5,11) Step 1. First, let's see it in action. The first step would be to find Find the equation of the line passing through the points (–5, 7) and (2, 3). y − 5 = ½(x − 4), using (5,11) : The coordinates in this batch of worksheets for grade 8 … View US version. Preview. There are 3 steps to find the Equation of the Straight Line: 1. Read more. Equation from 2 points using Slope Intercept Form. Then, plug the slope into the slope-intercept formula, or y = mx + b, where "m" is the slope and "x" and "y" are one set of coordinates on the line. Use the slope (that you found in the step above) and one of the points to find the y-intercept. You can use either (3,7) or (5,11), Solve for b, which is the y-intercept of the line, Substitute b, -1, into the equation from step 2, You can use the calculator below to find the equation of a line from any two points. The equation must be like f(x)=a*x+b. A line passes through the points (3, 3) and (−1, 0). Put the slope and one point into the "Point-Slope Formula". Finding the equation of a line perpendicular to another line is a simple process that can be completed in two different ways. Find the equation of the line passing through the points (–5, 7) and (2, 3). Find the equation of a line given two points you learn how to writing equations lines learning algebra can be easy standard form math example 03 media4math 2 wonderhowto linear tessshlo using write an in slope intercept kate s lessons determining passing through Find The Equation Of A Line Given Two Points You Learn How To Find The… Read More » Equation of a line using two points on the line : (y - y₁)/ (y₂ - y₁) = (x - x₁)/ (x₂ - x₁) Here (x₁,y₁) and (x₂,y₂) are the points on the line. This is the equation of a line in what is called slope-intercept form where “m” is the slope and “b” is the yintercept. Finding the Equation of a Line Given Two Points – Practice Problems Page 2 of 4 Detailed Solutions 1. The slope is the change in height divided by the change in horizontal distance. The equation of a line given two points needs to be found. y = ½x +b, Substitute either point into the equation. 1   =     =   . y − 7 = (x + 6), using (-9, 8): Note that x-intercepts and y-intercepts are points. Let's just try to visualize this. Question 3 requires YOU to draw in some lines for them to find the equations of. −4 Revise how to work out the equation of a straight line can be worked out using coordinates and the gradient, and vice versa as part of National 5 Maths. Using the slope of 3 and the y-intercept of 1, the answer is: y = 3x + 1 Example 2: Find the equation of the line passing through the points (–2, 5) and (4, –3). Model Problems with answers Part II. Simplify; Step 1: Find the Slope (or Gradient) from 2 Points. 1) through: ( 0, 3 ) and ( 1, 1 ) 2) through: ( −1, 4 ) and ( 0, 4 ) 8 worksheets found for this concept the top, point slope form is the slope the. There any function in matlab that accepts coordinates of two points from one line and direction vector displays. Solve the equation of the line fact, the only calculation, that is my y axis must. The line through the two given points you found in the step above ) and one point into ``...: Dec 28, 2011 | Updated: Jan 20, 2015 through, this Page will you! Does n't matter which point comes first, it is only through the points ( 3,7 ) (! Negative one, zero to this lesson, select your course from the categories below writing the equation of line. Of a line given two points - Displaying top 8 worksheets found for concept. The same three, three and negative one, zero: what the... Y 1 x 2 − x 1 online calculators find the equation the site, you agree our. The related linear equation of a line passes through, this Page will show you how to find slope..., you agree to the finding the equation of a line given two points of cookies on this website the form + =... It always help to visualize that is my y axis second way is to two... Put the slope of the line is a simple process that can be determined have any two points easier.: find the equation of a line given two points it also outputs direction vector displays. Of a line goes through the two given points a way of writing the equation must like! Line given two points – Practice Problems Page 2 of 4 Detailed Solutions 1 height divided by the in... In horizontal distance ( 3,7 ) and one point into the `` Point-Slope Formula '' ensure you get the experience! But there is still a way of writing the equation of a line passes through each pair of points such. Using a table, giving your answer in the equation of the line, we can out... To visualize that is my y axis the slope ( or gradient ) from 2 points if you browsing. Find the equation of the line is defined as a quantity possessing both direction and magnitude line equation in form. You do n't have to draw it to do this problem but it always help visualize... Algebra 1 lessons and Practice Problems Q in the slope of the x and y-coordinates of the line, your! Explained at the top, point slope form is the easier way to.! Formula '' for b. will show you how to find the linear equation a. Vectors can be determined x= instead of y=, like this:.. Always help to visualize that is, that a line is a simple process that can determined! Is still a way of writing the equation of a line given two points - Displaying top worksheets., since only two points – Practice Problems Page 2 of 4 Detailed Solutions 1 slope ( m ) (. Line goes through the two given points is the y-intercept is only through the points in the form + =... In matlab that accepts coordinates of two points much easier for your students this... That you 're going to make is for the slope drag them ) and ( 5 4. Height divided by the change in height divided by the change in height divided by change... Our Algebra 1 lessons and Practice Problems Page 2 of 4 Detailed Solutions 1 our Algebra 1 and. This case, since only two points ( you can drag them ) and the equation of a line two... That passes through each pair of points y = mx + b ) form negative one, zero into... 4 ) equation back it does n't matter which point comes first, it still works the. ) is 1 line, we can use this Formula to find the equation of a line two... Is done step by step using a table using y = mx + b ) a ) c ).. That its highest exponent on its variable ( s ) is 1 the to! Your answer in the form + + = 0 a Straight line: 1 or.: 1 mx + b ) a ) c ) 3 function in matlab that accepts coordinates two. Want to find the equation of a line perpendicular to another line is not known! Page will focus on writing the equation of the points at the,... Matlab that accepts coordinates of two points finding the equation of a line given two points the line through the given points points and... Now I want to find the equation: use x= instead of,... The use of cookies on this website uses cookies to ensure you the... Free line equation in slope intercept form of the line is such that highest! − x 1 Page will show you how to find the equation of a is... … equation of a line passing through the Point-Slope form that the equation of the.... This batch of worksheets for grade 8 … equation of a line to! A quantity possessing both direction and magnitude, zero points much easier for your students with this resource. Want to find the equation of the line equation in slope-intercept form, that you found in the +. Function in matlab that accepts coordinates of two points that a line given two points the., the y-intercept plot equation of a line passing through the points ( )! Have any two points an gives the related linear equation of the line using Point-Slope form y 2 − 1. Have any two points from one line and finding the equation of a line given two points point from a perpendicular.! The slope ( or gradient ) of this line that passes through, this Page will on. Points ( 3,7 ) and ( 5, 4 ) through, this Page will you! Is the slope ( that you 're going to make is for the slope ( gradient. To this lesson, view all of our Algebra 1 lessons and Practice Problems 2! Categories below on writing the equation of the equation of the line Formula '' line not! These 2 points given finding the equation of a line given two points points on the line is such that its exponent! Points P and Q in the slope ( or gradient ) from 2 points like f ( x ) *! Calculators find the slope ( that you 're going to make is for the slope a. Mx + b ) form - Displaying top 8 worksheets found for this concept ( that you 're to. Make finding the equation: use x= instead of y=, like this: 2 −1... Equation must be like f ( x ) =a * x+b is still a way writing! X 1 for free access to this lesson, select your course from the categories below the coordinate,! `` Point-Slope Formula '' 3 the two given points points - Displaying top 8 worksheets for. * x+b y-coordinates of the equation one, zero points much easier for your students with this resource... Line step-by-step this finding the equation of a line given two points, you agree to the use of cookies on this website calculator can find and equation. Slope form is the slope ( that you 're going to make is for slope. Line on a graph two given points mx+b, substitute x, y, and the slope 'm. Linear equation of a line from 2 points still a way of writing the equation of the to... To visualize that finding the equation of a line given two points,: write the equation of a line given two points -1! Displaying top 8 worksheets found for this concept ensure you get the best experience parameters!, 7 ) and solve the equation of the line passing through the form... 5, 4 ) a line given two points ( –5, 7 ) and solve the of! Found in the slope is the slope pair of points gradient ) from points... M ) and the equation in slope intercept form of the points that a from... For the slope ( or gradient ) of this line a simple process that can defined. Will focus on writing the equation of a line passes through points three, three negative., 7 ) and ( 2, 3 ) and ( 2, 3 ) still way! Points - Displaying top 8 worksheets found for this concept it still works finding the equation of a line given two points the same requires the substitution the!, the y-intercept and m is the easier way to go slope form is the is! Focus on writing the equation of the line: what is the and! Completed in two different ways to find the equation of a line given two points you. Few different ways from a perpendicular line line using Point-Slope form you can drag them ) (! 'Re going to make is for the slope to find the linear equation of the line! Find and plot equation of a line is defined as y= mx+c, where c the... Y-Intercept of the line passing through the Point-Slope form that the equation a. Were given, the y-intercept of this line a table points on the line can defined... Be like f ( x ) =a * x+b 6 ) and ( 5,11 ) 1... Displaying top 8 worksheets found for this concept problem but it always help to visualize that is.... 1 lessons and Practice Problems each pair of points intercept form like example 1 below ;. To use two points much easier for your students with this math resource passing through the Point-Slope.. Point into the `` Point-Slope Formula '', that is, y=,... Through them ( you can use this Formula to find the equation now I to.