B)10.08 cm²
The small triangle is an isosceles triangle therefore both sides are 3.2 cm long. The total length of the base is therefore 6.3+3.2 which is 9.5 cm. The area of the larger triangle is therefore ½×9.5×3.2=15.2 cm².
Area of small triangle is ½×3.2×3.2=5.12 cm².
Minus area of small triangle from area of large triangle.
15.2-5.12= 10.08 cm²