The perpendicular bisector of the line segment connecting the points $(-3,8)$ and $(-5,4)$ has an equation of the form $y = mx + b$. Find $m+b$.
Midpoint = (-4,6)
Slope = (4 - 8)/(-3 - 5) = 1/2
Perpendicular bisector: y - 6 = -2(x + 4) = -2x - 8
==> y = -2x - 2
m + b = -4
+335 
