Answer:
240 square feet
Explanation:
The area of a composite figure can be found by adding the areas of its parts.
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Extending the vertical line across the figure cuts off a rectangle on the left that is 18 ft long and 10 ft high. It cuts off a triangle on the right that has a base of 20 ft and a height of 24-18 = 6 ft.
The sum of the areas of these parts is ...
rectangle area + triangle area
= (10 ft)(18 ft) +1/2(20 ft)(6 ft) = 180 ft² +60 ft²
= 240 ft² . . . . area of the figure
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Additional comment
You can see that this is the product of the height of the rectangle and the overall length of the figure. This means the smaller triangles that stick above or below the horizontal lines would fit exactly into the spaces at the tip of the arrow, filling in a 10 ft × 24 ft rectangle.