If the area of ABCD is 90 square units, what is its perimeter?

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

Elizabeth claims that the fourth root of 2 can be expressed as 2^m since (2^m)^n = 2. find the values of m and n for the case where elizabeth's claim is true.

Mr. thompson is on a diet. he currently weighs 260 pounds. he loses 4 pounds per month. what part of the story makes the relationship not proportional?