One angle of a parallelogram measures 42°. What are the measures of the other three angles

in the parallelogram?

1 answer

Since opposite angles in a parallelogram are congruent, the opposite angle to the 42° angle also measures 42°. Therefore, the two opposite angles are both 42°.

The sum of the angles in a parallelogram is 360°. If we subtract the two congruent 42° angles, we are left with 276° for the other two angles.

Since opposite sides in a parallelogram are parallel, the other two angles are also congruent. Therefore, we can divide the 276° by 2 to get the measure of each of these angles:

276°/2 = 138°

So the other three angles in the parallelogram each measure 138°.