( 1)△PAQ ~△BPR;
(2)QR? =AQ RB .
Prove:
1)∫△PQR is an equilateral△
∴∠QRP=∠PRQ=∠PQR=60
∫∠APB = 120
∴∠apq+∠bpr= 120-∠prq =∠pqr =∠apq+∠a = 60
∴∠BPR=∠A
∴∠b=∠prq-∠bpr=60-∠a =∠apq∠pqa =∠BRP = 120
∴△PAQ~△BPR。
2)∫△PAQ ~△BPR;
∴AQ/PR=PQ/RB
PR = PQ = QR
∴AQ/QR=QR/RB
∴QR? =AQ RB .