The perimeter of a rectangle is equal to 24
. If the length is halved and the width is tripled, the new perimeter is increased by 8
. What is the length of the original rectangle?

Respuesta :

Answer:

The length of the original rectangle is 8.

Step-by-step explanation:

If we call w the width and call L the length of the rectangle then the perimeter is calculated by the following equation:

[tex]2w+2L=P[/tex]

In this case we know that the perimeter P is: P=24

Then:

[tex]2w+2L=24[/tex]

If we call the new width of the rectangle w 'then

[tex]w '= 3w[/tex]

If we call the new length of the rectangle L 'then

[tex]L '= 0.5L[/tex]

Therefore:

[tex]2w'+2L'=24[/tex]

[tex]2(3w)+2(0.5L)=24+8[/tex]

[tex]6w+L=32[/tex]

Now solve we have the following system of equations

[tex]2w+2L=24[/tex]

[tex]6w+L=32[/tex]

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To solve the system multiply the first equation by -3 and add it to the second equation

[tex]-6w-6L=-72[/tex]

[tex]6w+L=32[/tex]

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[tex]-5L=-40\\\\L=\frac{-40}{-5}\\\\L=8[/tex]