I can't seem to find a formula to find the perpendicular bisector of a line. Anyone know what it is?
The slope of the line through A and B is . So the slope of your perpendicular bisector is 5, since the two slopes will multiply to give -1.
The midpoint of AB is
So the perpendicular bisector is of the form with and a point it passes through is . Substituting these gives
and so the equation of your perpendicular bisector is .