Question

∆ ABC~∆DEF and ar(∆ABC) =4ar(∆DEF). If BC=12 find EF​

Answer 1

Answer:

EF=6

Step-by-step explanation:

the triangles are similar

therefore, ratio of area of triangles is equal to square of corresponding sides.

ar(∆ABC)=4ar(∆DEF)

ar(∆ABC)/ar(∆DEF)=4/1

Ar.of ∆abc/ar.of triangle ∆def =(BC)^2/(EF)^2

4/1=12^2/(EF)^2

4/1=144/EF^2

(EF)^2=144/4

(EF)^2=36

EF=6