Answer:
x = -1, x = 1
Step-by-step explanation:
Factor the equation. (It's a difference of squares, so we know the form will be (a-b)(a+b).)

Test this by FOILing it out, if you're unsure. This is something it can be good to memorize!
Set it equal to 0.

Separate the two parenthetical expressions by the Zero Product Property.

Solve for x!

Answer:
a. pi
Step-by-step explanation:
5280/25, ignoring the remainder, equals 211. That's the answer