Question

In the following figures, find the area of the shaded region.

Answer 1

(i) Area of rectangle ABCD = (10 cm x 18 cm) = 180 cm²

Area of triangle I = 12×6×10 cm² = 30 cm²
Area of triangle II = 12×8×10 cm² = 40 cm²
∴ Area of the shaded region = {180 - ( 30 + 40)} cm² = { 180 - 70}cm² = 110 cm²
(ii) Area of square ABCD = (Side)² = (20 cm)² = 400 cm²

Area of triangle I = 12×10×20 cm² = 100 cm²
Area of triangle II = 12×10×10 cm² = 50 cm²
Area of triangle III = 12×10×20 cm² = 100 cm²
∴ Area of the shaded region = {400 - ( 100 + 50 + 100)} cm² = { 400 - 250}cm² = 150 cm²