Question

Find the area of an isosceles triangle whose equal side measure 13 cm and whose base measure 20 cm​

Answer 1

We have,

Three sides13cm,13cm and 20cm.

By using Heron's formula

We need to get the semi-perimeter

s= a+b+c/2 = 13+13+20/2

= 46/2 =23

Now,

put the heron's formula,

s= √s(s−a)(s−b)(s−c)

= √23(23−13)(23−13)(23−20)

= √23×10×10×3

=10 √23×3

=83.07cm²