If the points (5, 4) and (x, y) are equidistant from the point (4, 5), prove that x2 + y2 - 8x - 10y +39 = 0.
Ans : AP = PB AP2 = PB2
(5 - 4)2 + (4 - 5)2 = (x - 4)2 + (y - 5)2
1 + 1 = x2 - 8x + 16 + y2 - 10y + 25 x2 + y2 - 8x - 10y + 41 - 2 = 0
x2 + y2 - 8x - 10y + 39 = 0