Notice that the weird figure looks like a rectangle that is missing a piece.
In this case, find the area of the rectangle... then subtract the area of the missing piece from that area of the rectangle.
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Area of rectangle: 4 x 5 = 20 sq. inches
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How to find the area of the missing piece:
- Notice that the other side is 2 inches while the left side is 4 inches, which means that if I subtract 2 from 4... then I will know the width of the missing piece.
- [4 - 2 = 2 inches is the width of the missing piece.]
- Notice that the top side is 4 inches while the bottom side is 5 inches, which means that if I subtract 4 from 5... then I will know the length of the missing piece.
- [5 - 4 = 1 inch is the length of the missing piece].
So, the area of the missing piece: A = lw = (1)(2) = 2 sq. inches
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Now, subtract the area of the missing piece from the area of the rectangle:
20 - 2 = 18 sq. inches
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ANSWER: 18 sq. inches