SOLUTION: The length of a rectangle is 2 in. more than twice its width. If the perimeter of the rectangle is 34 in., find the dimensions of the rectangle.

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Question 102926: The length of a rectangle is 2 in. more than twice its width. If the
perimeter of the rectangle is 34 in., find the dimensions of the rectangle.

Found 2 solutions by bucky, MathLover1:
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Let L represent the length and W represent the width.
.
You are told that L equals 2 inches more than 2W. In equation form this is:
.
L = 2W + 2
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Next you are told that the perimeter (P) is 34 inches. The perimeter is found by adding all
the sides. In other words:
.
P = L + W + L + W
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By combining like terms on the right side this can be simplified to:
.
P = 2L + 2W
.
Substitute 34 for the perimeter to get:
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34 = 2L + 2W
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But since L = 2W + 2 we can substitute 2W + 2 for L in the perimeter equation to get:
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34 = 2(2W + 2) + 2W
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Multiply out the right side by finding the product of 2 and each of the terms inside
the parentheses. When you do, the equation becomes:
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34 = 4W + 4 + 2W
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Get rid of the 4 on the right side by subtracting 4 from both sides to get:
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30 = 4W + 2W
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Combine terms on the right side to reduce the equation to:
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30 = 6W
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Solve for W by dividing both sides by 6 to get:
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5 = W
.
So we know the width is 5 inches. But our first equation tells us that the Length is
twice the width plus 2 inches ... or 2 times 5 and then add 2. This makes the length 12
inches.
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In summary, the width is 5 inches and the length is 12 inches.
.
Check by adding the 4 sides: 5 + 12 + 5 + 12 to get 34 inches for the perimeter, just as
it should be.
.
Hope this helps you to understand the problem and how to solve.
.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
if
+length=+a
width+=+b
Perimeter = P = 34+in
Since P+=+2%28a+%2B+b%29
and a is 2+in more than twice its width, we can write
a+=+2%2Ab+%2B+2+in
Then:
P+=+2%282%2Ab+%2B+2+in+%2B+b%29
Or
34+in+=+4b+%2B+2b+%2B+4+in
34+in+%96+4+in+=+6b
6b+=+30+in
b+=+30%2F6+in
b+=+5+in => a+=+2%2A%2810+in+%2B+2+in%29=+12+in
check:
P+=+2%2812+in+%2B+5+in+%29+
P+=+2%2A17+in+
P+=+34+in+