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George is building a fence around a rectangular dog run. He is using his house as one side of the run. The area of the dog run will be 240 square feet. The length of the run is 30 feet, and the width is 30 - x feet. The diagram below shows his plan.

Recall the formulas for area and perimeter: A = lw and P = 2l + 2w.
]How many feet of fencing will George need for the dog run?

2 Answers

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Answer: 76 feet of fencing will George need for the dog run.

Explanation:

Area of rectangular dog run = 240 square feet

Length of the rectangle dog run : 30 feet

Width of the rectangular dog run : 30 -x feet

Area of rectangle = length × width

240 squared feet = 30 feet × (30 - x) feet

x = 22

The width of the rectangular dog run = 30 -x feet = 30 - 22 feet = 8 feet

The perimeter of rectangle = 2(lenght + width)

Perimeter of rectangular dog run = 2(30 + 8) = 76 feet

76 feet of fencing will George need for the dog run.

User Vitall
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30 x (30-x) = 240
30-x = 8
-x = -22
x = 22

Therefore width is 30-22 = 8 feet

8+8+30+30 = 76

Thus, George would need 76 feet of fencing for the dog run
User Ahawtho
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9.0k points