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Mateo used 14 meters of fence for a rectangular pen alongside his house. He only needs to fence three sides such that the length is 1 meter more than triple the width. He decides to put the longer side length along the house as shown.What is the area of the pen?

Mateo used 14 meters of fence for a rectangular pen alongside his house. He only needs-example-1
User Ahs N
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1 Answer

22 votes
22 votes

Let's begin by listing out the information given to us:

Mateo used 14m of fence total

He fences 3 sides

Length is 1 more than three times the width:


l=1+3w

The sum of the length of one side & width of 2 sides. We proceed to calculate for the length and width as shown below:


\begin{gathered} 14=l+w \\ But,l=1+3w \\ \Rightarrow14=1+3w+w \\ \Rightarrow14=1+4w \\ 14-1=4w\Rightarrow13=4w \\ 4w=13 \\ w=(13)/(4)=3(1)/(4) \\ w=3(1)/(4)m \\ \\ l=1+3w\Rightarrow l=1+3(3\frac{1}{4_{}}) \\ l=1+9(3)/(4)=10(3)/(4) \\ l=10(3)/(4)m \end{gathered}

The Area of the rectangle is given by:


\begin{gathered} A=l\cdot w=10(3)/(4)\cdot3(1)/(4) \\ A=(43)/(4)\cdot(13)/(4)=(559)/(16) \\ A=34(15)/(16)=34.9375\approx35m \\ A=35m \end{gathered}

User Georgiy Chebotarev
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