Question

Lines m and n are perpendicular. If the slope of m is zero, then the slope of n is

zero
undefined
negative

Answer 1

Undefined

Explanation:

You can deduce the solution in two ways: if the slope of m is zero, it is horizontal. So, n is vertical because it must be perpendicular to n. Vertical lines have undefined slope.

Alternatively, if the slope of line m is k, the slope of a perpendicular line n is -1/k. So, if k=0, you can't compute -1/0.

Answer 2

The slope of n should be Undefined