Answer
$$y-20=-\frac{1}{3}(x-15)$$
Work Step by Step
We first find the slope:
$$m=\frac{29-20}{-12-15}=-\frac{1}{3}$$
We know that point slope form is expressed as $y-y_1=m(x-x_1)$, where $(x_1,y_1)$ is a point on the line, and m is the slope of the line. Using this, we find that the equation of the line is:
$$y-20=-\frac{1}{3}(x-15)$$
