Answer:
x = 2
Step-by-step explanation:
Perimeter of triangle = a + b + c
Perimeter of rectangle = 2(l + b)
=> x + 5 + x + 6 + x + 7 = 2(2x - 1 + x + 7)
=> 3x + 18 = 2(3x + 6)
=> 3x + 18 = 6x + 12
=> 3x - 6x = 12 - 18
=> -3x = -6
=> x = -6/-3
=> x = 2
