Answer:
25°
Step-by-step explanation:
If sides PS and QR are parallel, then ∠PSQ and ∠RQS are alternate interior angles, hence congruent. That is, ∠PSQ ≅ ∠RQS = 25°.
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Comment on the problem statement
Confirming that two sides are parallel does not confirm the figure as a parallelogram. It could be a trapezoid. The given condition is necessary, but is not sufficient to do the confirmation.
