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प्रश्न
The areas of two similar triangles ABC and PQR are in the ratio 9:16. If BC = 4.5cm, find the length of QR.
उत्तर
It is given that Δ ABC ~ Δ PQR
Therefore, the ration of the areas of triangles will be equal to the ratio of squares of their corresponding sides.
`(ar(ΔABC))/(ar(ΔPQR))=(BC^2)/(QR^2)`
⇒` 9/16=4^2/(QR^2)`
⇒` QR^2=(4.5xx4.55xx16)/9`
⇒ `QR= (sqrt(4.5xx4.5xx16))/9`
`= (4.5xx4)/3`
= 6 cm
Hence, QR = 6 cm
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