What is eight more than a number is less than 12

The product of two negative rational numbers is always zero sometimes zero never zero

Find the measure of the interior angles of the following regular polygons: a triangle, a quadrilateral, a pentagon, an octagon, a decagon, a 30-gon, a 50-gon, and a 100-gon.

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