Need help and show work plz

Explanation:

With any parallelogram, the adjacent angles always add to 180 degrees.

(angle ADC) + (angle DCB) = 180

(angle ADC) + 120 = 180

angle ADC = 180 - 120

angle ADC = 60 degrees

Angles 1 and 2 combine to form angle ADC by the angle addition postulate. This is just the idea of gluing smaller angles to form larger ones.

(angle 1) + (angle 2) = angle ADC

45 + (angle 2) = 60

angle 2 = 60-45

angle 2 = 15 degrees