What is the value of x in the diagram below?

Complete the standard form of the equation that represents the quadratic relationship displayed above, where a, b, and c are rational numbers.

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 the diagram polygon abcd is a reflection across ef to make polygon a'b'c'd'.