Mr. Weber

It is the same as (x^2 - 9).  It is called a, "difference of perfect squares. The answer is: (x + 3)(x - 3).

This is a trigonometry question. It is rare for a teacher to ask such a question. It can be figured out using trig functions, namely tangent.

Here are some examples: The slope for 0 degrees is 0. For 30 degrees, slope = .5774. For 45 degrees, slope = 1. For 60 degrees, slope = 1.7321. For 90 degrees, slope = undefined (infinity).

You should memorize 0, 45, and 90 degrees.

Good luck!