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Area as a function of x = Domain of the function of the area =

Area as a function of x = Domain of the function of the area =-example-1

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To answer this question we first, have to put the length of the rectangle in terms of x. We know that the total area is 150 ft², and that the area of a rectangle is given by:


A=\text{width}\cdot\text{length.}

Solving the above equation for the length, and substituting width=x, and A=150, we get:


\text{length}=(150)/(x)\text{.}

Now, the length of the interior rectangle is:


(150)/(x)-8,

and the width of the interior triangle is:


x-4.

Therefore, the area of the interior triangle is given by the following expression:


(x-4)((150)/(x)-8)\text{.}

Now, to determine the domain, we know that the sides of the interior rectangle must fulfill the following inequalities:


\begin{gathered} x-4>0, \\ (150)/(x)-8>0. \end{gathered}

Therefore,


\begin{gathered} x>4, \\ (150)/(x)>8, \\ 150>8x, \\ (150)/(8)>x\text{.} \end{gathered}

Answer:

Area as a function of x


(x-4)((150)/(x)-8)\text{.}

Domain:


(4,(75)/(4))\text{.}

User SgtHale
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