The shaded areas of the figure may be found by subtracting the area of the unshaded portion from the total area of the figure. Use this approach to find the area of the shaded portion.
A rectangle contains two equally sized cut-outs of triangles. The bases of the two triangle cut-outs make up the top side of the rectangle. The base of each triangle has length 55 centimeters and a height of 36 centimeters. The width of the rectangle is 76 centimeters.
55 cm55 cm
55 cm55 cm
36 cm36 cm
76 cm76 cm
(two congruent triangles within a rectangle)
A =
▼
cm squaredcm2
cm cubedcm3
cm
shaded area = (area of rectangle) - 2(area of triangle)
area of rectangle = length * width = (55 + 55) * 76 = 110 * 76 = 8360 cm2
area of triangle = (1/2) * base * height = (1/2) * 55 * 36 = 990 cm2
shaded area = 8360 cm2 - 2(990) cm2 = 8360 cm2 - 1980 cm2 = 6380 cm2