Question

if one of sides of an isosceles triangle is 20cm greater than its equal side and perimeter is 200cm. Then find the area of the given figure.

Answer 1

Step-by-step explanation:

let the equal sides be x

one side is 20cm longer so... = x+20

perimeter of isosceles triangle = sum of all sides

200 = x+x+x+20

200 = 3x+20

200-20 = 3x = 180 =3x

180/3 = x = 60 cm...

so it's equal sides are of 60cm..

and other side is 80cm...

area of the traingle using heron's formula

s = a+b+c /2

200 /2 = 100cm.

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

$\sqrt{100(100 - 60)(100 - 60(100 - 80)}$

$\sqrt{100 \times 40 \times 40 \times 20}$

$\sqrt{10 \times 10 \times 40 \times 40 \times 20}$

$10 \times 40 \sqrt{20}$

$400 \sqrt{20} cm ^{2}$

OR

400*4.471 = 1788.4 cm² approx..

thank you

hope it helps ❤️❤️