The perimeter of a triangle is 72 cenimeters.the second side is twice as long as the first side.the third side is four centimeters shorter than the second side.how long is the first side?

Answer 1

Let the first side length be A, etc.

A + B + C = 72
B = 2A
C = B-4

B/2 + B + (B -4) = 2.5 B -4 = 72
2.5 B = 76
B = 30.4
A = 15.2 is the first side length
C = 26.4
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Sum = 72, as required