Question

what is the slope of a line perpendicular to a line with a slope of 0

Answer 1

Slope is undefined for vertical lines.

Answer 2

The slope would be infinite | undefined, depending on which term you prefer.

Answer 3

Undefined is mathematically preferred because if you call it infinite, is it +∞ or -∞?

Answer 4

so my answer would be undefined

Answer 5

You probably want to call it undefined, just in some cases it might be beneficial to consider it as infinite as well.

Answer 6

That's probably best. I've also heard it said that vertical lines have no slope, but this is often confused with having zero slope. Having a slope of zero is not the same as not having a slope.
"Undefined" is probably best.

This is best explored using slope formula, and trying to put a vertical line into y=mx+b form.
(There will be difficulties).

Answer 7

It comes down to the old division-by-zero problem: how much nothing can you fit into something? As much as you want, really.. and you don't know if that amount is positive or negative, so even saying "infinity" is misleading because you don't know if it should be positive infinity or negative infinity.

Answer 8

thnks