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Question
In ∆ABC, B – D – C and BD = 7, BC = 20, then find the following ratio.
`(A(∆ABD))/(A(∆ABC))`
Solution
Draw a perpendicular from vertex A to line BC.
`(A(∆ABD))/(A(∆ABC)) = ((1/2) xx AX xx BD)/((1/2) xx AX xx BC)`
= `(BD)/(BC)`
= `7/20`
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(iii) `"A(ΔADC)"/"A(ΔABC)"`
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If ΔABC ∼ ΔDEF, length of side AB is 9 cm and length of side DE is 12 cm, then find the ratio of their corresponding areas.
In the figure, PQ ⊥ BC, AD ⊥ BC. To find the ratio of A(ΔPQB) and A(ΔPBC), complete the following activity.
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Therefore,
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= `square/square`
