If the shorter piece is x feet long, the longer piece is 3x+4 feet long, and the total length is
... x + (3x+4) = 36
... 4x = 32 . . . . . . . . simplify, subtract 4
... x = 8
The shorter piece is 8 feet long; the longer piece is 28 feet long.
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You can do the math for the longer piece in your head: 36 ft - 8 ft = 28 ft.
