Question

please solve this one

ABC lll DEF and their areas are respectively 64cm square and 121 cm square. if EF= 15.4 cm find BC.

Answer 1

For this problem we use the theorem-Areas of similar triangles will be equal to square of corresponding sides.

Triangle ABC is similar to Triangle DEF (given)

Therefore

⇒ ar(Triangle ABC)/ar(Triangle DEF)=(BC/EF)²

⇒64/121=(BC/15.4)²

⇒64x15.4x15.4/121=BC²

⇒125.44=BC²

⇒√125.44=BC

⇒∴11.2 cm=BC

Hope this helps!