+819 Write the equation for the perpendicular bisector of the line segment connecting the points $(3,2)$ and $(-1,7)$ in the form $y = mx + b$.
Note: The perpendicular bisector of the line segment $\overline{AB}$ is the line that passes through the midpoint of $\overline{AB}$ and is perpendicular to $\overline{AB}$.
+18 first find midpoint of line
(((x1+x2)/2),((y1+y2)/2))
= (((3-1)/2),((2+7)/2))
= (1,9/2)
equation of original line
1. find slope (7-2)/(-1-3) = -5/4
2. write in point slope form: y - 2= -5/4(x - 3)
3. expand into slope intercept form: y = -5/4x + 23/4
find slope of perpendicular line, which is -1/m, where m is original slope
-1/(-5/4) = 4/5
equation of perpendicular line passing through (1,9/2): y = 4/5x + 23/4
