How Wide is the Garden?Date: 01/06/98 at 20:46:21 From: Megan Breen Subject: Pre Algebra-word problems Shawn puts a fence around the perimeter of a rectangular garden. He uses 136 feet of fencing. The garden is 40 feet long. How wide is it? Date: 01/08/98 at 11:24:54 From: Doctor Jennifer Subject: Re: Pre Algebra-word problems Hello Megan! First you have to see what kind of information was given to you. You were given the amount of fencing that was used (perimeter), the length of one side, and the fact that it was a rectangular garden. Now examine what each piece means. The length of fencing is the perimeter. What is the perimeter? The perimeter is the sum of the sides of the rectangle. Next think about what a rectangle is. A rectangle is a four-sided figure with 2 sets of equal sides and 4 right angles. Finally, you know the length of one side. You can set up an equation: x+x+y+y = p x - one side of the rectangle y - other side of rectangle p - perimeter Then you have the equation x+x+40+40 = 136. Then you can simplify: 2x+80 = 136 Finally, you solve for x: 2x+80-80 = 136-80 Subtract 80 from both sides in order to get the x term alone: 2x = 56 Then divide both sides by 2 do get the x alone: 2x/2 = 56/2 x = 28 Looking back at the chart, you now know that x is the length of the missing side and that the garden is a 40 x 28 rectangle. Hope this information is helpful. If you have any more questions just ask. -Doctor Jennifer, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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