At a meeting of musicians, 56 of the musicians play the piano but only 35 play the violin. What is the minimum number of people at the meeting who play both piano and violin?

M∠abc=138° and m∠def=31° . which statement is true about ∠abc and ∠def ? a: the angles are neither complementary nor supplementary. b: the angles are complementary. c: the angles are supplementary.