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The John Hancock Center in Chicago has a rectangular base. The length of the base measure 65ft less than twice the width.

The perimeter of this base is 860ft. What are the dimensions of the base?

1 Answer

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Answer:

265 ft long, 165 ft wide

Explanation:

Let w represent the width of the base. Then the length is 2w-65. The perimeter is ...

P = 2(L+W)

860 = 2((2w -65) +w)

430 = 3w -65 . . . . . . . . divide by 2, simplify

495 = 3w . . . . . . . . . add 65

w = 165 . . . . . . . . divide by 3

2w -65 = 330 -65 = 265 . . . . . find the length

The base is 265 ft long and 165 ft wide.