Question

Find every point on the horizontal line
y = 5
that is a distance of 5 units away from the point
(6, 1).

Answer 1

well, you know that the vertical distance from (6,1) to y=5 is 4.

So, using a 3,4,5 triangle, the two points are 3 horizontal units away from (6,5), at

(3,5) and (9,5)

If you use your distance formula, you can verify that both of these points are 5 units away from (6,1).