CPM Homework Help : AC Problem 7-74

Sometimes the quickest and easiest two points to use to graph a line that is not in slope-intercept form are the $x$ - and $y$ -intercepts. Find the $x$ - and $y$ -intercepts for the two lines below and then use them to graph each line. Write the coordinates of the $x$ - and $y$ -intercepts on your graph.

$x-2y=4$

$3x+6y=24$

Hint:

The $y$ -intercept is the value of $y$ when $x$ is $0$ .

Steps:

To find the $y$ -intercept, substitute $0$ for $x$ and evaluate.
$\begin{array}{r} 0 - 2y = 4 \; \; \; \\ -2y = 4 \; \; \; \\ y = -2 \end{array}$
The $y$ -intercept is $(0,-2)$ . Now do the same for the $x$ -intercept, but substitute $0$ for $y$ instead.

More Help:

Plot the two intercepts and draw the line to connect them.
Label the intercept points.