CPM Homework Help : GC Problem 7-120

Below are the equations of two lines and the coordinates of three points. For each line, determine which of the points, if any, lie on that line. (There may be more than one!)

$X(0,15)$ $Y(3,16)$ $Z(7,0)$

$y=\frac{1}{3}x+15$
Hint (a):
Individually check to see if $X$ , $Y$ , and $Z$ are on the line.
Do this by substituting the given coordinates into the original equation.
There may be more than one point correct.
Step 1(a):
$15=\frac{1}{3}(0)+15$
$X$ is on the line.
Step 2(a):
$16=\frac{1}{3}(3)+15$
$Y$ is on the line.
Step 3(a):
$0\neq \frac{1}{3}(7)+15$
$Z$ is not on the line.

$y-16=−4(x-3)$
Hint (b):
Follow the same procedure in part (a).