In the above diagram, there are 4 triangles and one square
Base of the triangle (b) = 2 cm
Height of the triangle (h) = 4 cm
Side of the square = 2 cm
Area of triangle = 1/2 bh = 1/2 x 2 x 4 = 4 cm²
Area of 4 triangles = 4 x 4 cm² = 16 cm²
Area of the square = 2 cm x 2 cm = 4 cm²
Surface area of the total shape = Area of 4 triangles + Area of the square = 16 cm² + 4 cm² = 20 cm²
