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Question
Triangles ABC and DEF are similar.
If area (ΔABC) = 36 cm2, area (ΔDEF) = 64 cm2 and DE = 6.2 cm, find AB.
Solution
Area (Δ ABC) = 36 cm2
Area (Δ DEF) = 64 cm2
DE = 6.2 cm
AB =?
We have
`"area (Δ ABC)"/"area (Δ DEF)" = "AB"^2/"DE"^2`
⇒ `(36)/(64) = "AB"^2/(6.2)^2`
⇒ AB = `(6)/(8)`
⇒ AB = `(6 xx 6.2)/(8)`
⇒ AB = 4.65 cm.
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