Answer:
30
Explanation:
RT is a transversal, and since the sides of the parallelogram are parallel, angle QTR is equal to angle SRT, so angle SRT is 30 degrees. Since the side opposite the 30 degree angle in a right triangle is equal to half the value of the hypotenuse, RS is double TS, making RS equal to 10. Since opposite sides of a parallelogram are congruent, QR = 5 and QT = 10. We add up all the values of the sides to get a perimeter of 30.