Question

Determine A, tal que P (2,a) seja equidistante dos pontos A (0,2) e B(2,0).

Answer 1

$d_{PA}=d_{PB}\\ \\ \sqrt{(2-0)^2+(a-2)^2}=\sqrt{(2-2)^2+(a-0)^2}\\ \\ 4+a^2-4a+4=a^2\\ \\ 8-4a=0\\ \\ \boxed{a=2}$