Question

Write an equation of a line that is parallel to y = 5. Write an equation of a line
that is perpendicular to y = 5. What do you notice about the equation of the
perpendicular line?

Answer 1

Answer: The perpendicular line intersects with the parallel line.

Perpendicular lines have negative reciprocal slopes to parallel lines, so it intersects with the parallel line.

Parallel line: y = 5x + 3

Perpendicular line: y = -1/5x - 4