In △ABC, <B=90, AB=12cm, and AC=15cm. D and E are points on AB and AC respectively such that <AED=90 and DE=3cm. Find:

i) Area of △ADE

ii) Area of quadrilateral BCED : Area of △ABC

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- Feb 3rd 2010, 02:29 AMsnigdhaSimilarity..help!
In △ABC, <B=90, AB=12cm, and AC=15cm. D and E are points on AB and AC respectively such that <AED=90 and DE=3cm. Find:

i) Area of △ADE

ii) Area of quadrilateral BCED : Area of △ABC - Feb 3rd 2010, 02:34 AMsnigdha
well....i managed to work out i) on my own- (Clapping)

△AED~△ABC->[by A.A. similarity rule]

So, ar△AED:ar△ABC= (DE/BC)^2

=> ar△AED: 1/2BC.AB=(3/9)^2

=> ar△AED= 54*1/9

= 6 sq.cm

So somebody now plz solve the ii) part for me...(Shake) - Feb 3rd 2010, 03:28 AMArchie Meade