Answer:
x = 4
Explanation:
Perimeter of triangle: P = (5x -1) + (5x -1) + (2.2x + 10)
Perimeter of square: P = 4(6.5x - 11.8)
so (5x -1) + (5x -1) + (2.2x + 10) = 4(6.5x - 11.8)
5x - 1 + 5x - 1 + 2.2x + 10 = 26x - 47.2
12.2x + 8 = 26x - 47.2
26x - 12.2x = 8 + 47.2
13.8x = 55.2
x = 55.2/13.8 = 4