Q19 of 47 Page 7

In ΔPQR, PS ⊥ QR and SR > SQ, show that PR > PQ.

PR > PQ
Construction: Draw PT such that SQ = ST
Proof: In ΔPQS and ΔPTS,
      PS = PS         ...... [common]
     SQ = ST          ......[By construction]
  ∠PSQ = ∠PST       ...... [each 90°]
... ΔPQS ≅ ΔPTS   ...... [SAS criterion]
...∠1 = ∠2                 ...... [c.p.c.t.]
Now in ΔPRT, we have the exterior angle ∠2
... ∠2 = ∠3 + ∠TPR
or ∠2 > ∠3
... ∠1 > ∠3 ...... (∠1 = ∠2)
Now in ΔPQR, since 
   ∠1 > ∠3
... PR > PQ ...... [side opposite to greater angle]

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