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The area of the shaded region is 42 ft2 . What is the area of the unshaded region? A) 7 ft 2B) 21 ft2C) 42 ft2D) 84 ft2

The area of the shaded region is 42 ft2 . What is the area of the unshaded region-example-1
The area of the shaded region is 42 ft2 . What is the area of the unshaded region-example-1
The area of the shaded region is 42 ft2 . What is the area of the unshaded region-example-2
User Trinie
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1 Answer

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Area of a Rectangle

Given a rectangle of width W and length L, its area can be calculated as:


A=W\cdot L

If we cut the rectangle by its diagonal, we get to congruent triangles, each one with half the area of the rectangle, that is:


A_t=(A)/(2)_{}

The shaded region corresponds to one of these triangles, thus the unshaded region must have the same area as the shaded region.

Area of the shaded region: 42 ft2

Area of the unshaded region: 42 ft2

Area of the rectangle: 84 ft2

User Cleison
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