Answer:
x = 6
Explanation:
Each side of the triangle = x cm
Each side of the square = (x - 1.5) cm
Given that the perimeter of both shapes are equal, thus, set the perimeter of the triangle equal to the perimeter of the square to solve for x.
Perimeter of triangle = 3(x) = 3x cm
Perimeter of square = 4(x - 1.5) = 4x - 6
Therefore:
Perimeter of triangle = perimeter of square
Substitute
3x = 4x - 6
Subtract 4x from each side
3x - 4x = -6
-x = -6
Divide both sides by -1
x = -6/-1
x = 6