What is the length of each side?

The longest side of a triangle is twice a long as the shortest side, which is 2cm shorter than the third side. What is the length of each side of the triangle if it's perimeter is equal to 38 cm?

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x = shortest side
2x = longest side  {longest side is twice as long as the shortest side}
x + 2 = third side  {the shortest side is 2 shorter than the third side}

x + 2x + x + 2 = 38  {the perimeter is equal to 38}
4x + 2 = 38   {combined like terms}
4x = 36   {subtracted 2 from each side}
x = 9   {divided each side by 4}
2x = 18   {substituted 9, in for x, into 2x}
x + 2 = 11   {substituted 9, in for x, into x + 2}

9 is the shortest side
18 is the longest side
11 is the third side

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