Question

triangle ABC &DEF are similar and their areas are 49 & 144 respectively EF=6cm find BC??

Pls answer it fst it’s argent......

Answer 1

You should know that if two triangles are said to be similar, their area increases as square of their sides,i.e.,

A is directly proportional to side²

Easier....i mean by saying if u doubke the sides of a triangle....its area increases by 2²=4 times the original area....

Therefore, if we compare,
A1/A2 = (s1/s2)²
49/144 = (BC/EF)²
(7/12)² = (BC/EF)²
7/12 = BC/EF
=> BC = 7/12 *EF
= 7/12 * 6 cm
= 7*2 cm
= 14 cm