

InterviewSolution
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In parallelogram ABCD. two points P and Q are taken on diagonal BD such that DP = BQ. Show that:(i) ∆APD ≅ ∆CQB (ii) AP = CQ (iii) ∆AQB ≅ ∆CPD (iv) AQ = CP (v) APCQ is a parallelogram. |
Answer» Data: In parallelogram ABCD, two points P and Q are taken on diagonal BD such that DP = BQ. To Prove: (i) ∆AAPD ≅ ∆CQB (ii) AP = CQ (iii) ∆AQB ≅ ∆CPD (iv) AQ = CP (v) APCQ is a parallelogram. Proof: ABCD is a parallelogram. (i) In ∆APD and ∆CQB, AD = BC (opposite sides) ∠ADP = ∠CBQ (alternate angles) DP = BQ (Data) ∴ ∆APD ≅ ∆CQB (ASA Postulate) (ii) AP = CQ (iii) In ∆AQB and ∆CPD, AB = CD (opposite sides) ∠ABQ = ∠CDP (alternate angles) BQ = DP (Data) ∴ ∆AQB ≅ ∆CPD (ASA Postulate) (iv) ∴ AQ = CP (v) In ∆AQPand ∆CPQ, AP = CQ (proved) AQ = PC PQ is common. ∴ ∆AQP ≅ ∆CPQ ∴ ∠APQ = ∠CQP These are pair of alternate angles. ∴AP || PC Similarly, AQ || PC ∴ APCQ is a parallelogram. |
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