Question

Clara is building a triangular garden. She wants the length of the longest side to be three more than twice as long as the length of the shortest side, and the third side will be twelve feet long. What expression could she write to determine the perimeter of the triangle if s represents the length of the shortest side? (Recall that perimeter is the distance around a shape.)

Answer 1

the length of the shortest side = s
the length of the longest side = 2s + 3
the third side = 12

perimeter = s + 2s + 3 + 12
                = 3s + 15  ←  answer