Rectangle dimensions

tiny7smom

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The length of a rectangle is 19 inches less than the perimeter. The area is 1,400 square inches. What are the dimensions?
 
Hello, tiny7smom!

There must be typo.
Please check the numbers in the problem.


The length of a rectangle is 19 inches less than the perimeter.
The area is 1,400 square inches.
What are the dimensions?

"Length is Perimeter minus 19."
. . \(\displaystyle L \;=\; (2L + 2W) - 19 \quad\Rightarrow\quad L\:=\:19 - 2W\) .[1]

"Area is 1400."
. . \(\displaystyle LW \:=\:1400\) .[2]

Substitute [1] into [2]: .\(\displaystyle (19-2W)W \:=\:1400 \quad\Rightarrow\quad 2W^2 - 19W + 1400 \:=\:0 \)

And this quadratic equation has no real roots.
 
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