In parallelogram ABCD, the measure of angle ABC is 8 times the measure of angle BCD. How many degrees are in the measure of angle ADC?
ABC + BCD =180
8 BCD + BCD = 180
9 BCD = 180
BCD = 180 / 9 = 20°
ADC = 180 - BCD = 180 - 20 = 160°
