Example 11.25 from Prealgebra, 11.3 Graphing with Intercepts

Graphing with Intercepts: example 11.25

Find the intercepts of $4 x - 0 = 12$

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution
To find the $x -intercept,$ let $y = 0 .$

$4 x - 3 y = 12$

Substitute 0 for $y .$ $4 x - 3 \cdot 0 = 12$

Multiply. $4 x - 0 = 12$

Subtract. $4 x = 12$

Divide by 4. $x = 3$

The $x -intercept$ is $(3, 0) .$

To find the $y -intercept,$ let $x = 0 .$

$4 x - 3 y = 12$

Substitute 0 for $x .$ $4 \cdot 0 - 3 y = 12$

Multiply. $0 - 3 y = 12$

Simplify. $−3 y = 12$

Divide by −3. $y = −4$

The $y -intercept$ is $(0, −4).$

The intercepts are the points $(−3, 0)$ and $(0, −4) .$

$4 x −3 y = 12$

x y

$3$ $0$

$0$ $−4$

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Find the intercepts of the line: $3 x −4 y = 12 .$

How did it go?