for an angle of 780°, we can say that is really a 360° + 360° + 60°, so two full revolutions plus an extra 60°. Check the picture below, with the coterminal in green.
Ok so for number 5, AB is proportional to BC just like PQ is proportional to QR. AB = 9, BC = 15, PQ = 3, and QR = x. 9/15 = 3/x. Cross Multiply: This gives you - 9x = 45. Divide both sides by 9, and you get x = 5. QR = 5
(n-2)multiple 180 degrees the formula for finding the sum of all angles in a polygon regular here n represents the number of sides of the polygon.
