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Length, Width of Rectangle Given Perimeter

Date: 9/4/96 at 21:41:17
From: Anonymous
Subject: Length, Width of Rectangle Given Perimeter

If the perimeter of a rectangle is 300 and the length is two times the 
width, what are the length and the width? 

Write an equation to show how you would work the problem.

Date: 9/4/96 at 21:44:24
From: Doctor Robert
Subject: Re: Length, Width of Rectangle Given Perimeter

Call the width of the rectangle x.  Then, if the length is two times 
the width, the length must be 2x.  Now, if you have a rectangle whose 
width is x and whose length is 2x, the perimeter must be 
2x+2x+x+x = 6x.  

You are told that the perimeter is 300, so the equation is 6x = 300. 
Dividing both sides by 6, one gets x = 50.  So the width is 50 and the 
length is 100.

-Doctor Robert,  The Math Forum
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Associated Topics:
Middle School Algebra
Middle School Geometry
Middle School Triangles and Other Polygons

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