Q(h, k) is the foot of the perpendicular of P(3, 6) on the line x - 2y + 4 =0.
If the slope of PQ is m, find m2.
PQ is r to the given line.
Slope of x - 2 y + 4 = 12
⇒ 12×m=−1
⇒ m = -2
⇒ m2=4
If Q is the foot of the perpendicular of the point P(3, 6) on the line x - 2y + 4 = 0, then the equation of PQ is