Answer: 334 square feet
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Step-by-step explanation:
Draw a vertical line through the middle to split the figure into two rectangles.
The rectangle on the left is 21 ft by 7 ft. Its area is 21*7 = 147 sq ft.
The rectangle on the right is 24-7 = 17 ft by 21-10 = 11 ft. The area is 17*11 = 187 sq ft.
The combined area is therefore: 147+187 = 334 square feet
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A different approach:
Draw a horizontal line through the middle to form two rectangles.
The rectangle on top is 10 ft by 7 ft with area of 10*7 = 70 sq ft.
The rectangle on the bottom is 24 ft by 12-10 = 11 ft, so its area is 24*11 = 264 sq ft.
Total area = 70+264 = 334 square feet
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Yet another method:
Draw a horizontal line through the top most edge of the figure. Do the same for the right-most side of the figure. The two lines meet in the top right corner. This will form a rectangle that is 21 ft tall and 24 ft wide.
The area of this big new rectangle is 21*24 = 504 sq ft.
However, we don't want all of this area. We'll kick out the rectangular piece that is 10 ft tall by 24-7 = 17 ft across (in the upper right corner). The area we want to kick out is 10*17 = 170 sq ft.
The actual area we want is 504 - 170 = 334 square feet
There are probably other methods you could use to find the area of this figure.