Question

在直线x-y+4=0上求一点上求一点P,使它到点M(-2,-4),N(4,6)的距离相等

Answer 1

(x+2)(x+2)+(y+4)(y+4)=(x-4)(x-4)+(y-6)(y-6)

4+4x+16+8y=-8x+16-12y+36

3x+5y-8=0

x-y+4=0

y=5/2

x=-3/2