Question

The perimeter of a Triangle(MNO) is equal to the perimeter of square ABCD. If the sides of the triangle are represented by 4x+4, 5x-3, and 17, and one side of the square is represented by 3x, find the length of a side of the square.

Answer 1

perimeter of square = 4(3x) = 12x
perimeter of triangle = 4x+4 + 5x-3 + 17 = 9x + 18

so
12x = 9x+18
3x=18
x=6

so the side of the square is 3(6) = 18

check:
perimeter of square = 4(18) = 72
sides of triangle are 28, 27 and 17
perimeter of triangle = 28+27+17 = 72

Answer 2

5x+3