SOLUTION: What is the area of a rectangle that has a perimeter of 47 mm and a length of 18.5 mm?

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Question 69586: What is the area of a rectangle that has a perimeter of 47 mm and a length of 18.5 mm?
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
To find the perimeter (P) of a rectangle you need to add 2 times the length (L) to 2 times the width (W) of the rectangle. In equation form this is written:
2L+%2B+2W+=+P
You are given that P is 47mm and L is 18.5mm. Substitute these values into the equation to get:
2%2A18.5+%2B+2W+=+47
Multiply out the 2*18.5 and the equation becomes:
37+%2B+2W+=+47
Subtract 37 from both sides to remove it from the left side of the equation. The result is:
2W+=+10
Finally, divide both sides by 2 and you find that:
W = 5 mm.
Then recognize that the area of a rectangle is found by multiplying its length times its width. You were given that the length was 18.5 mm and you found that the width was 5 mm. Multiplying these two together results in an area (A) equal to:
A+=+18.5%2A5
which multiplies out to:
A+=+92.5
and the units of the answer are square mm