Q4 of 95 Page 6

If ΔABC ~ ΔDEF, AB =10 cm, area (ΔABC) = 20 sq. cm, area (ΔDEF) = 45 sq. cm. Determine DE.

Given: ABC ~DEF, AB = 10cm,

and area of ABC = 20 sq cm , area of DEF = 45 sq cm


We know that, the ratio of two similar triangles is equal to the square of the ratio of their corresponding sides.



[given]




⇒(DE)2 = 5 × 45


⇒ DE = 15cm


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