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प्रश्न
If ∆ABC ~ ∆DEF such that area of ∆ABC is 9 cm2 and the area of ∆DEF is 16 cm2 and BC = 2.1 cm. Find the length of EF.
उत्तर
Given ∆ABC ~ ∆DEF
∴ `("Area of" Delta"ABC")/("Area of" Delta"DEF") = "BC"^2/"EF"^2` ...(Square of their corresponding sides)
`9/16 = (2.1)^2/"EF"^2`
`(3/4)^2 = (2.1/"EF")^2`
`3/4 = 2.1/"EF"`
EF = `(4 xx 2.1)/3` = 2.8 cm
Length of EF = 2.8 cm
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