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The width of a small rectangular playground is 3 meters less than the length ofthe playground.If the area of the playground_5,1 square meters, what are the dimensions ofthe playground? State the units of the dimensiops. Make sure you reject the answer thatcannot be a solution.You MUST solve this problem using a quadratic equation. Draw a diagram that representsthe problem.

The width of a small rectangular playground is 3 meters less than the length ofthe-example-1
User Kamisha
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1 Answer

13 votes
13 votes

Taking l and w as the length and the width of the rectangle respectively, we have that:


w=l-3

We know that the area of a rectangle is:


A=w\cdot l

Replace A for the given value of the area and w for the expression stated:


54=(l-3)\cdot l

Solve the operations and write the equation as a quadratic expression:


\begin{gathered} 54=l^2-3l \\ 0=l^2-3l-54 \end{gathered}

Solve the quadratic equation using factorization:


\begin{gathered} 0=(l-9)(l+6) \\ l-9=0 \\ l=9 \\ l+6=0 \\ l=-6 \end{gathered}

For this context, the value of l that we can use is 9. It means that the length of the triangle is 9m.

Use this value and the first expression to find w:


\begin{gathered} w=l-3 \\ w=9-3 \\ w=6 \end{gathered}

The width of the triangle is 6m.

The width of a small rectangular playground is 3 meters less than the length ofthe-example-1
User Otra
by
3.1k points
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