Question

The first side of a triangle is 7 ft more than the third side. The second side is 1 ft shorter than 3 times

Answer 1

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Answer:

  8 ft

Step-by-step explanation:

Let t represent the length of the third side. The first side is 7 ft more, so is (t +7). The second side is 1 ft shorter than 3 times the third side, so is (3t -1). The perimeter is the sum of the side lengths:

  21 = (t +7) +(3t -1) +t

  21 = 5t +6

  15 = 5t . . . . . . . subtract 6

  3 = t . . . . . . . divide by 5

Then the length of the second side is ...

  3t -1 = 3·3 -1 = 8 . . . . feet

The length of the second side is 8 feet.

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Additional comment

The first side is 3+7 = 10 ft. So the three side lengths are 10 ft, 8 ft, 3 ft.