Question

find the area of isosceles triangle is the perimeter is 11 cm and the base is 5 cm

Answer 1

We know that ,

Two sides of an isosceles triangle is equal

So, 5cm+x+x=11

5cm+2x=11

2x=11cm-5cm

2x=6cm

x=3cm

So equal sides =3cm

Area of the isosceles triangle =√5.5(5.5-3)(5.5-3)(5.5-5)

=√5.5×2.5×2.5×0.5

=√17.1875

=4.146 cm^2