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The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?

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.

Complete the solution of the equation. find the value of y when x equals to 1 9x-5y=29