Answer:
#18) <em>m</em>∠B = 107°
#19) <em>m</em>∠B = 17°
Step-by-step explanation:
*Supplementary angles are angles who's measures equal 180°
*Complementary angles are angles who's measures equal 90°
#18) If ∠A is 73°, then we must subtract 73 from 180.
180 - 73 = 107
This means that <em>m</em>∠B = 107°.
#19) If ∠A is 73°, then we must subtract 73 from 90.
90 - 73 = 17
This means that <em>m</em>∠B = 17°.