One side of a triangle is one-third the longest side. the third side is 11 ft less than the longest side. the perimeter is 73. find all 3 sides

side 1 = x

side 2 = x-11

side 3 = 1/3x

x + x-11 + 1/3x = 73

2x-11 + 1/3x = 73

2x = 6/3x

6/3x+1/3x = 7/3x

7/3x-11 = 73

7/3x = 84

7x = 84*3

7x = 252

x = 252/7

x = 36

longest side = 36

2nd side = 1/3 (36) = 12

3rd side = 36-11 = 25