How do I find the equation of a line between two points?

The equation of a line is written in the form y=mx+c where m is the gradient of the line and c is the y-intercept. These are the two values that we will need to calculate.For example, lets take the two points (2,2) and (6,4). We will label the two coordinates so that (2,2) is no.1 and (6,4) is no.2.To find the gradient, or slope, of the line we use the formula m=(y2-y1)/(x2-x1) where x1 is the x coordinate of no.1 and so on. Therefore, m=(4-2)/(6-2)= 1/2So we can now update our equation y=mx+c by substituting the m value to give y=0.5x+cTo find the c value, or the y-intercept, we then take one of our coordinates (either will work!)So for example, taking no.1, (2,2) and using x=2 and y=2 we can put this into our updated equation y=0.5x+c to give 2=(0.52)+cSolving this for c we get c=1 and then putting this into our equation we get y=0.5x+1 which is the line equation needed.

LR
Answered by Lucille R. Maths tutor

3154 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Two simultaneous equations are given as 2x + y = 5 and 3x + y = 7. Find the value of x and y.


Kenny has £3200 in a savings account. After a year, the bank pays him interest increasing his balance to £3360. What percentage rate was applied to the account?


Sketching a quadratic


Solve the following simultaneous equations: x^2 + y^2 = 12, x - 2y = 3


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences