We know that each angle is 720/n
Formula for each interior angle of polygon is 180(n-2)/n
The number of sides in the polygon are "m", so sub in m into the formula:
180(m-2)/m which is equivalent to 720/n each angle in the polygon
:. 180(m-2)/m = 720/n
divide both sides by 180
(m-2)/m=4/n...