I am working through this problem and I noticed that this problem is very advanced. The only two side lengths are 6x centimeters, and -3x + 18. Could anyone help for X
Well, we know that the lengths of a square are all equal. So 6x must be equal to -3x + 18.
6x = -3x + 18.
Add 3x to both sides to get: 9x = 18
Divide both sides by 9 to get x =2.
x =2.
And the perimeter would be 8 cm.
+213 
