Can someone please give an explanation on how to do this problem?

Question

Write an equation of the line passing through point p that is perpendicular to the given line

(4,-6), y=-3

Answer 1

y = -3 is the equation of the horizontal line passing through (0, -3).

The line that is perpendicular is a vertical line. The equation of a vertical line is in the form x = k.

To pass through the point (4, -6) the equation is x = 4.