Answer
$y-y_1=m(x-x_1)$
Work Step by Step
RECALL:
The point-slope form of a line's equation is:
$y-y_1=m(x-x_1)$
where m = slope and $(x_1, y_1)$ is a point on the line.
Thus, the missing expression in the given statement is:
$y-y_1=m(x-x_1)$
