Question

What is an equation of a line through (4,5) that is perpendicular to `y= 1/2x + 3`? Please show working.

Answer 1

`y = -2x + 13`

Explanation:

`r: y = ax + b` is perpendicular to `s: y = -1/a + c`

Your `r` has `a = 1/2`.

`(4,5) in s: y = -2x + c`

`5 = -2 * 4 + c`

`c = 13`