SOLUTION: I need to know if I did this correct? Algebra (perimeter) Dale Mayfield has decided to fence off a garden plot behind his house, using his house as the "fence" along one side o

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Question 753920: I need to know if I did this correct?
Algebra (perimeter)
Dale Mayfield has decided to fence off a garden plot behind his house, using his house as the "fence" along one side of the garden. The length (Parallel to house) is 3 feet less than twice the width. Find the dimensions if 33 feet of fencing is used along the three sides requiring it.
I got width=39/6
length=10
I took 33=2(2w-3)+2w
Is this correct
Found 2 solutions by josgarithmetic, Edwin McCravy:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
x=length and w=width

x=2w-3 three feet less than twice the width.

Fencing used is 1%2Ax%2B2%2Aw=highlight%282w-3%2B2w=33%29
4w-3=33
4w=36
highlight%28w=9%29 width

Finding value for x:
x=2%2A9-3
x=18-3
highlight%28x=15%29 length

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
Sorry, what you have is NOT correct. You tried to use the 
perimeter of a rectangle formula P = 2L + 2W.  But that 
particular perimeter formula is only good when there are 
FOUR sides of fencing, not when there are only THREE sides 
of fencing, as this problem states: 

      ___HOUSE, NO FENCE__
        |              | 
       W|              |W 
        |______________|
             2W-3

So you must use this 
formula instead:

LEFT SIDE + FRONT SIDE + RIGHT SIDE = TOTAL LENGTH OF FENCE
    ↓           ↓            ↓               ↓
    W     +   2W-3     +     W      =       33 

Answer:  W = 9 feet,  Length = 2W+3 = 2(9)+3 = 18+3 = 21 feet        

Edwin