GCSE Maths | Equation of a Line

• equation of a straight line: y = mx + c
  • x: horizontal axis
  • y: vertical axis
  • m: gradient = change in y/ change in x between any two co-ordinates
  • c: y-intercept
• To find the y-intercept
  • make x=0 and solve for y
• To find the x-intercept
  • make y=0 and solve for x
• To find the intersection of two lines
  • equate each line and solve for x or y

Question 1

Write down the gradient of each line

Question 2

Write down the y-intercept of each line

Question 3

Write down the equation of each line

Question 4

Write the equation of each line in the form y = mx + c

Question 5

Work out the x-intercept of each line

Question 5

Work out the gradient between the two points

Question 6

Work out the gradient of the line

Question 7

Work out the equation of each line

Question 8

Find the co-ordinates where the two lines intersect

Question 9

Find the gradient of a line that is

(i) paralllel

(ii) perpendicular