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Question
In figures, find the length CF.
Solution
BD = AF
BD = 10 cm
In Δ BCD, we have
tan 30° = `"CD"/"BD"`
`1/sqrt3 = "CD"/10`
CD = `(10 xx sqrt3)/3` cm
CF = CD + DF = `(10 xx sqrt3)/3 + 2 cm`
= `(10 xx sqrt3 + 6)/3 cm`
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