Final answer:
In a parallelogram, opposite angles are equal. Therefore, if U = 9x + 15 and V = 6x + 15, angles W and X will also be 6x + 15 and 9x + 15, respectively.
Step-by-step explanation:
The question is asking to find the angle measures of the remaining interior angles in a parallelogram given two of its interior angle expressions. In parallelograms, opposite angles are equal. Therefore, if U = 9x + 15 and V = 6x + 15, then angle W, being opposite to V, will also be 6x + 15, and angle X, being opposite to U, will be 9x + 15.