Question

Suppose points A, B, and C have the coordinates given below. Find y such that C is on the perpendicular bisector of segment AB.
A(−1, 4), B(7, −2), C(9, y)

Answer 1

AB has slope -6/8 = -3/4 and length 10.

So, we want a line with slope 4/3, passing through the midpoint (A+B)/2 = (3,1)

When x = 9, it's 6 units to the right of point A. So, y will be 4/3*6=8 units above point A, at 12. So, C=(9,12)

Answer 2

wrong