360/# of sides
Central angle of a circle is the same as the measure of the intercepted arc. davids1: more importantly the formulae for a central angle is π=pi, R=radius Central Angle= Arc Length x 180 / π x R
Central Angle An angle in a circle with vertex at the circle's center.
(n-2)*180 this is formula for findout the angles.now it is nonagone ,so it having 9 sides.so answer is7*180=1260
180