Q3 of 77 Page 15

Compute the area of trapezium PQRS in Fig. 15.76.

We have,

Area of trapezium PQRS = Area of rectangle PSRT + Area (Δ QRT)


Area of trapezium PQRS = PT * RT + (QT * RT)


= 8 * RT + (8 * RT)


= 12 * RT


In Δ QRT, we have


QR2 = QT2 + RT2


RT2 = QR2 - QT2


RT2 = (17)2 - (8)2


= 225


= 15


Hence,


Area of trapezium PQRS = 12 * 15


= 180 cm2


More from this chapter

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1

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