Which quantity could be used in the blank to make the equation true? 3x + x + = 8x

a) 3x b) 4x c) 5x d) x2

In the equations, a and b represent the price per night for a room in hotel a and hotel b, respectively, w weeks after september 1 last autumn. what was the price per night in hotel a when it was equal to the price per night in hotel b? a = 240 − 20w b = 320 − 30w

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.

Asphere has a diameter of 10 in. what is the volume of the sphere?