Q13 of 95 Page 6

In the given figure, DE || BC and DE : BC = 4 : 5. Calculate the ratio of the areas of ΔADE and the trapezium ΔCEDB.

It is given that DE || BC and DE : BC = 4 : 5

Let ∆ ADE and ∆ABC


∠ADE = ∠ABC [corresponding angles]


∠AED = ∠ACB [corresponding angles]


∴ ∆ ADE ~ ∆ABC [by AA similarity]


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



Subtracting 1 from both the sides, we get


[given]




⇒


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