Graphing Equations of LinesUsing x- and y-Intercepts

Find the x-intercept• The x-intercept is the point where the graph of the

equation crosses the x-axis. • The coordinate will be (x, 0) where the x will be the

point on the x-axis where it crosses. • To find the x-intercept of an equation, substitute the

value of 0 into the equation for the y value. Example:

0

2 3 12

2 3( ) 12

2 12

6

x y

x

x

x

By substituting 0 for y in the equation, we find the x-intercept which is (6,0). This becomes your first point on the graph.

Find the y-intercept• The y-intercept is the point where the graph of the

equation crosses the y-axis. • The coordinate will be (0, y) where the y will be the

point on the y-axis where it crosses. • To find the y-intercept of an equation, substitute the

value of 0 into the equation for the x value. Example:

2 3 12

2( ) 3 12

3

0

12

4

x y

y

y

y

By substituting 0 for x into the equation, we find the y-intercept which is (0,4). This becomes your second point on the graph.

The Graph2x+3y=12

Series 1

-8 -6 -4 -2 2 4 6 8

-8

-6

-4

-2

2

4

6

8

x

y

(6,0)

(0,4)

We found the point (6,0) for the x-intercept and (0,4) for the y-intercept. When graphing equations of lines, this method works for every graph.

Remember

To find the x-intercept, let the value of y equal 0 in the equation.

To find the y-intercept, let the value of x equal 0 in the equation.