What is the value of y?
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This is because quadrilateral JMQP is also a parallelogram. Note the arrow markers to tell us that JM is parallel to PQ, and also JP is paralle to QM.
A parallelogram has its opposite sides parallel, and those opposite sides are the same length.
JM = PQ and JP = QM
Because y = QM, QM = JP, and JP = 3, this means y = 3.