Let ABC be the isosceles triangle and AD be the altitude
Let AB = AC = x. Then, BC = (32 - 2x).
Since, in an isosceles triangle, the altitude bisects the base,
so BD = DC = (16 - x).
In triangle ADC,
BC = (32- 2x) = (32 - 20) cm = 12 cm.
Hence, required area =