Question

in a triangle abc,d ,e and f are , respectively the mid points of bc,can and ac are 7 cm,8cmand 9 cm, respectively,find the perimeter ​

Answer 1

Given: AB = 7 cm, BC = 8 cm, AC = 9 cm

  In a ΔABC, D, E and F are, respectively,

the mid points of BC, CA and AB. 

According to Midpoint Theorem: 

EF = 1/2BC, DF = 1/2 AC and DE = 1/2 AB 

Now, Perimeter of ∆DEF = DE + EF + DF  = 1/2 (AB + BC + AC)  = 1/2 (7 + 8 + 9)  = 12 

Perimeter of ΔDEF = 12 cm.

Answer 2

Answer:

the perimeter of ΔDEF is 12 cm.

Step-by-step explanation:

By using Midpoint Theorem, we get

Perimeter of ΔDEF = DE + EF + DF

                                =1/2AB+1/2BC+1/2AC

                                =1/2(7+8+9)

                                =24/2

                                =12cm