+2 votes
in Class 9 by kratos

In Fig., ABCD is a parallelogram and BC is produced to a point Q such that AD = CQ. If AQ intersect DC at P, show that ar(∆BPC) = ar(∆DPQ). (Hint: Join AC).

1 Answer

+6 votes
by kratos
 
Best answer

Data : ABCD is a parallelogram and BC is produced to a point Q such that AD = CQ. AQ intersect DC at P,

To Prove: ar.(∆BPC) = ar.(∆DPQ)

Construction: AE is joined.

Proof: ABCD is a parallelogram.

∆APC and ∆BDC are on BC and in between AB || PC.

∴ ∆APC = ∆BPC …………… (i)

In this fig. AD || CQ and AD = CQ (Data)

∴ ∆BCD is a parallelogram.

∆DQC and ∆AQC are on base QC and in between QC || AD.

∴ ∆DQC = ∆AQC ar.(∆DQC) – ar.(∆PQC) = ar.(∆ACQ) – ar.(∆PQC)

∴ ar.(∆APC) = ar.(∆DPQ) ………….. (ii)

Comparing (i) and (ii),

ar.(∆BPC) = ar.(∆DPQ).

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