Q20 of 168 Page 5

If D is a point on the side AB of such that AD : DB = 3.2 and E is a point on BC such that . Find the ratio of areas of .

20.jpg


We have


AD/DB=3/2


In BDE and BAC


∠B=∠B [Common]


∠BDE=∠A [Corresponding]


BDEBAC


Area() =AB2


Area () BD2


=52/22 [AD/DB=3/2]


=25/4


Area()


Area () =25:4


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