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21. A rectangle has an area of x2 + 3x – 4 and a width of X - 1. What is the length of the rectangle? I A.X + 4 B. X – 4 C. X + 2 D. x - 2

User Deimoks
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1 Answer

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The area of a rectangle is given by:


\begin{gathered} A=w\cdot l \\ where \\ w=width_{}=x-1 \\ l=length \\ A=Area=x^2+3x-4 \end{gathered}

So:


\begin{gathered} l=(A)/(w) \\ l=(x^2+3x-4)/(x-1)=((x-1)(x+4))/((x-1))=x+4 \end{gathered}

User Jari Laamanen
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