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Question 652531:  The length of a rectangular room is 6 feet longer than twice the width. If the room's perimeter is 152 feet, what are the rooms dimensions? 
 Answer by Shana-D77(132)      (Show Source): 
You can  put this solution on YOUR website! Ok, so let's start by translating this problem literally:
 
"The length of a rectangular room is 6 feet longer than twice the width" 
L =  2w  + 6  (remember "=" reads as "is")
 
"If the Perimeter is 152 feet" 
P = 152
 
We know that the perimeter of a rectangle is L + L + W + W or 2L + 2W
 
So, we have 152 = 2L + 2W
 
Our two equations are then: 
L = 2w + 6 
2L + 2w = 152
 
Since the first equation is solved for L, let's get the second equation also solved for L:
 
2L + 2w = 152 
L + w = 76  (dided everything by 2) 
L = 76 - w  (subtracted w from both sides)
 
Now we have: 
L = 2w + 6 
L = 76 - w
 
Since they're both =L, they're equal to each other (transitive peoperty):
 
2w + 6 = 76 - w
 
3w + 6 = 76 (added w to both sides)
 
3w = 70 (subtracted 6 from both sides)
 
w = 70/3 or 23.333 feet (23 feet, 4 inches)
 
To find L, we can plug our w back into any of the equations we used.  The easiest may be the 152 = 2L + 2w equation:
 
152 = 2L + 2(70/3) 
152 = 2L + 140/3 
316/3 = 2L    (subtracted 140/3 from both sides) 
L = 158/3 (52.66 feet or 52 feet and 8 inches)
 
w = 23 feet, 4 inches 
L = 52 feet, 8 inches 
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