Question

find all points having an x-coordinate of 2 whose distance of the point (-1-2)is 5.

Answer 1

all points having a distance of 5 from (-1, -2) lie on a circle with equation
(x+1)^2 + (y+2)^2 = 25
you want the x to be 2
3^2 + (y+2)^2 = 25
(y+2)^2 = 16
y + 2 = ± √ 16 = ± 4

if y+2 = 4, then y = 2
if y+2 = -4, then y = -6

so your points are (2,2) and (2,-6)