Question

find the area of a triangle whose sides are in the ratio 3:5:7 and
whose perimeter is 300cm​

Answer 1

Answer:

by using heron's formulae you can find the area of the triangle

Step-by-step explanation:

let the sides be 3x 5x and 7x

perimeter = 300cm

3x+5x+7x= 300

x=300÷15

x= 20

3x=60 (a)

5x=100 (b)

7x=140 (c)

semiperimeter (s)= 300÷2=150

area= root(s(s-a)(s-b)(s-c))

=root(150×90×50×10)

=root(3×5×5×2×3×3×2×5×5×2×5×5×2)

=5×5×5×3×2×2 root 3

=1500(root3) cm^2

I hope this is the answer

even if it is not use the above formula

Answer 2

Answer:

1500√3 cm sq.

Step-by-step explanation:

Let the three sides be 3x, 5x, 7x

Perimeter of a triangle = 300 (Given)

3x + 5x + 7x = 300

15x = 300

x = 20

Now the sides of a triangle are = 3*20, 5*20, 7*20

= 60, 100, 140

s = 300/2

= 150

Area =

$\sqrt{s(s - a)(s - b)(s - c)} \\ = \sqrt{150(150 - 60)(150 - 100)(150 - 140)} \\ = \sqrt{150(90)(50)(10)} \\ = \sqrt{(5 \: \times 3 \times 10)(3 \times 3 \times 10)(5 \times 10)(10)} \\ = \sqrt{100 \times 5 \times 3 \sqrt{3} } \\ = 1500 \sqrt{3} cm {}^{2}$