SOLUTION: If the length of the rectangle is twice the width,and the perimeter of the rectangle is 30cm, what is the length and width of the rectangle.

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Question 852382: If the length of the rectangle is twice the width,and the perimeter of the rectangle is 30cm, what is the length and width of the rectangle.
Answer by JulietG(1812) About Me  (Show Source):
You can put this solution on YOUR website!
L = 2W (length of the rectangle is twice the width)
2L + 2W = 30 (the perimeter of the rectangle is 30cm [perimeter is a fence])
Substitute the value of L from the first equation into the second
2(2W) + 2W = 30
Multiply
4W + 2W = 30
Ad
6W = 30
Divide each side by 6
W=5
.
If W = 5, then L =10.
Let's prove it by building a perimeter fence. We'll need two lengths and two widths. 5 + 5 + 10 + 10 = 30
Success!