There is a 5 x 6 garden with a 2 feet wide walkway that goes around it. So, there are 2 feet on each side of the the 5 x 6.
5+2+2 = 9
6+2+2 = 10
Now we have a 9 x 6 and the parameter would equal
9*2 + 6*2
18 + 12 = 30 feet of fencing
So we would need 30 feet of fencing.