We know that all three angles in a triangle must add to 180 degrees so we can use this fact to find the measure of the missing angles.
180-57-101= 22 degrees
180-72-72=36 degrees
180-x-20=160-x degrees
A) 1 out of 4
B) 1 out of 4
First subtract 2 revolutions from the - 840 :- (- (840-720) = -120
This gives sin -120 which is in the 3rd quadrant of the unit circle
sin -120 = - sin 60 = - sqrt3/2
Answer:
Step-by-step explanation: