Question

The sides of a triangular plot are in the ratio 5 : 7 : 9 and its perimeter is 420m. 3
Find its area.

Answer 1

Answer:

side a = 5x

side b = 7x

side c = 9x

perimeter = 420

side a +side b + side c =  420

5x + 7x + 9x =  420

21x = 420

x = 420/21

x = 20

Therefore,,

side a = 5x = 5 X 20 = 100 m

side b = 7x = 7 X 20 = 140 m

side c = 9x = 9 X 20 = 180 m

Now,

s= (a+b+c)/2

s= 420/2

s=210 m

Using Heron Formula,

ar. =

$\sqrt{s(s-a)(s-b)(s-c)}$$\sqrt{s(s-a)(s-b)(s-c)}$$\sqrt{s(s-a)(s-b)(s-c)}$$\sqrt{s(s-a)(s-b)(s-c)}$= $\sqrt{s(s-a)(s-b)(s-c}$

$\sqrt{210(210-100)(210-140)(210-180)}$

please solve further from here. As there is problem in inserting roots and other values right now in my system.

thank you