Basic Geometry : How to find the length of the side of a rectangle
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Example Question #1 : How To Find The Length Of The Side Of A Rectangle
The rectangle below has a perimeter of 54. Find the lengths of the unknown side. That is, find S.
11
7
17
3
5
7
For a rectangle, its perimeter is the sum of all for sides. We can write
Simplify
Solve for S
Example Question #1 : How To Find The Length Of The Side Of A Rectangle
Given a rectangle with a length 
The given rectangle has a length that is 
Since the area of the rectangle is equal to its length multiplied by its width (
Replacing 
Distribute the variable into the parentheses.
Factor the polynomial.
Example Question #1 : How To Find The Length Of The Side Of A Rectangle
There is a regtangular fence surrounding a park. The perimeter of the fence is 
The formula for the perimeter of a rectangle is:
We know the perimeter of the rectange is 
Example Question #2 : How To Find The Length Of The Side Of A Rectangle
A rectangle has a perimiter of 36 inches and a length of 12 inches. What is the width of the rectangle in inches?
To find the width, multiply the length that you have been given by 2, and subtract the result from the perimeter. You now have the total length for the remaining 2 sides. This number divided by 2 is the width.
Example Question #1 : How To Find The Length Of The Side Of A Rectangle
A rectangle four and a half times as long as it is wide has perimeter of 272 centimeters. To the nearest tenth of a centimeter, how wide is it?
If we call the width of this rectangle 
The perimeter can then be written as:
Since the perimeter of the rectangle is 272 cm, we can set up the following equation:
Example Question #1 : How To Find The Length Of The Side Of A Rectangle
The width, in cm, of a rectangular fence is 2 more than half its length, in cm. Which of the following gives the width, w cm, in terms of length, l cm, of the rectangular fence?
w = 2l – 2
w = 2l + 2
w = ½ l – 2
w = ½ l + 2
w = ½ l + 2
To find the width, we must take half of the length, which means we must divide the length by 2. Then we must take 2 more than that number, which means we must add 2 to the number. Combining these, we get:
w = ½ l + 2
Example Question #1 : How To Find The Length Of The Side Of A Rectangle
The width of a rectangle is 2 inches longer than 3 times its length. Which of the following equations gives the width, w, of the rectangle in terms of its length, l,?
w = 1/3l +2
w = 3l + 2
w = 3l – 2
w = 6l +2
w = 3l + 2
The width equals 3 times the length, so 3l, plus an additional two inches, so + 2, = 3l + 2
Example Question #2 : How To Find The Length Of The Side Of A Rectangle
Your dad shows you a rectangular scale drawing of your house. The drawing is 6 inches by 8 inches. You're trying to figure out the actual length of the shorter side of the house. If you know the actual length of the longer side is 64 feet, what is the actual length of the shorter side of the house (in feet)?
36
81
60
32
48
48
We can solve this by setting up a proportion and solving for x,the length of the shorter side of the house. If the drawing is scale and is 6 : 8, then the actual house is x : 64. Then we can cross multiply so that 384 = 8x. We then divide by 8 to get x = 48.
Example Question #2 : How To Find The Length Of The Side Of A Rectangle
If the perimeter of a rectangle is 
Recall how to find the perimeter of a rectangle.
We can then manipulate this equation to find the width.
Now, plug in the information given by the question to find the width.
Example Question #1 : How To Find The Length Of The Side Of A Rectangle
If the perimeter of a rectangle is 
Recall how to find the perimeter of a rectangle.
We can then manipulate this equation to find the width.
Now, plug in the information given by the question to find the width.
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