Answer:
84 cm²
Explanation:
Surface area of the polyhedron = the sum of the areas of each parts of the net = area of 2 triangles + area of each of the 3 rectangles
Area of 2 triangles:
Base = 4 cm
Height = 3 cm
Area of the 2 triangles = 2(½*base*height)
= 2(½*4*3) = 4*3 = 12 cm²
Area of rectangle with the following dimensions:
Length = 6 cm
Width = 4 cm
Area = length * width = 24 cm²
Area of rectangle with the following dimensions:
Length = 6 cm
Width = 5 cm
Area = length * width = 30 cm²
Area of rectangle with the following dimensions:
Length = 6 cm
Width = 3 cm
Area = length * width = 18 cm²
Surface area of the polyhedron = 12 + 24 + 30 + 18 = 84 cm²