Q9 of 62 Page 186

In the figure, DE || BC and , calculate the value of

(i) (ii)



i) In ΔADG and ΔABF


∠ADE = ∠ABC by corresponding angles (DG∥BF)


∠AED = ∠ACB by corresponding angles (DG∥BF)


∴ ΔADE ∼ ΔABC


Let AD = 3x, so BD = 5x.




----(1)


Similarly, ΔADG ∼ ΔABF




----(2)


Now,


(by (1) and (2)) ----(3)


ii) Area of BCED = Area of ΔABC – Area of ΔADE


(by (3))




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