Question 905866
Good day student. I hope this will be helpful to you.I wish I knew what the answer you got was so I could see what you did wrong, but here is how I did it.  
first you write down information in the problem which is as follows:
P=54
L=2w it is important to write it down so you don't get confused as you work the problem. 
You also need to know the formulas for area and perimeter of a rectangle. 

A=LW and P=2L +2w

we are going to work with the perimeter formula first to solve for L and W.
 
Using the formula p=2L +2w you can substitute the information from the problem into the formula.

54=2L +2W 
now substitute 2w for L and solve for w
 54= 2(2w) + 2w
distribute the 2 in front of the parenthesis as follows:
54=4W + 2w
combine like terms
54=6w
since we want to isolate w, we have to divide both sides by 6
54/6=6w/6  the sixes on the right side cancel out and we are left with just w
9=w 
from the problem we know that L=2w so to get the length you substitute 9 for w and get L=2(9) multiply and you get L=18

now we use the formula for area A=LW and substitute the values of 9, 18 for the respective variable:

A=(9)18 multiply
A=162 meters 

I hope that this is helpful to you. If you desire paid assistance, please contact me through my websitewww.facebook.com/tutoringinquiry or online through www.instaedu.com or via email at mbarre1@wgu.edu. I will be happy to discuss my services in detail with you.Have a great day.