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Question
If ΔABC ~ ΔPQR, AB : PQ = 4 : 5 and A(ΔPQR) = 125 cm2, then find A(ΔABC).
Solution
Given: ΔABC ~ ΔPQR
We know that,
`("A"(Δ"ABC"))/("A"(Δ"PQR")) = ("AB")^2/("PQ")^2` ......[Theorem of area of similar triangles]
∴ `("A"(Δ"ABC"))/125 = (4)^2/(5)^2`
∴ `("A"(Δ"ABC"))/125 = 16/15`
∴ A(ΔABC) = `16/25 xx 125`
∴ A(ΔABC) = 80 cm2
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