Question

Triangles ABC and DEF are similar.
If area (ΔABC) = 36 cm², area (ΔDEf) = 64 cm² and DE = 6.2 cm, find AB.

Answer 1

Area (ΔABC) = 36 cm²
Area (ΔDEF) = 64 cm²
DE = 6·2 cm
AB =?
We have
`"area (ΔABC)"/"area (ΔDEF)" = "AB"^2/"DE"^2`
⇒ `(36)/(64) = "AB"^2/(6.2)^2`
⇒ `"AB"/(6·2) = (6)/(8)`
⇒ AB = `(6 xx 6·2)/(8)`
⇒ AB = 4·65 cm.