The area of the big blank triangle = (10+12) ×12 ÷ 2 =132cm2.

The area of the smallest blank triangle = (12-10) ×12 ÷ 2 =12cm2.

The area of the blank triangle = 10 × 10÷2=50 square centimeters.

Shadow area = sum of areas of two squares and-three blank triangles.

The sum of the areas of two squares =10×10+12×12 = 244 square centimeters.

The sum of the areas of three blank triangles =132+12+50 =194cm2.

Shadow area =244- 194=50 cm2.