#### Answer

length of sides of isosceles triangle = 10cm

#### Work Step by Step

altitude of an isosceles triangle = h =8cm
perimeter = p =32cm
and side = a cm
then h =$1\div$2$\sqrt (p(4a-p))$
16 = $\sqrt (32(4a-32))$
16 = 8 $\sqrt(2a-16)$
2= $\sqrt(2a-16)$
4= 2a-16
2a=20
a= 10 cm