How do I do this? I don’t understand it

Step-by-step explanation:

x+65 = 180                            Consecutive angles in llgm are supplementary

x = 180-65                             Subtract equal amounts from both sides.

x = 115

y + 65 = 90                           This hard to explain without letters. The lines are parallel. The right angle is an extension of the right vertical parallel line. So the left two angles are 90 degrees because of the perpendicular angles.

y = 90 - 65

y = 25