Answer: 18 Centimeters
Step-by-step explanation: The area of the figure is
2x^2 + 2(x+5)^2 + x(x+5)
= 2x^2 + 2x^2 + 20x + 50 + x^2 + 5x
= 5x^2 + 25x + 50,
and this is 120 cm^2,
so x^2 + 5x + 10 = 24 =>
x^2 + 5x - 14 = 0 =>
x = 2, (as x can't be -7).
The perimeter of the original rectangle is
4+14=18 CM