Answer:
x = 3.5
perimeter of each figure = 54
Step-by-step explanation:
Perimeter of square: 4(3x + 3) 12x + 12
Perimeter of equilateral triangle: 3(5x + 0.5) = 15x + 1.5
Solve for x: 12x + 12 = 15x + 1.5
Grouping like terms results in 10.5 = 3x, which leads to x = 3.5.
Each polygon has a perimeter of 12x + 12, which here is 12(3.5) + 12 = 54
x = 3.5
perimeter of each figure = 54
