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How do I simplify the rational expression,2x-8÷2x^2+2x-40?

User Tmcallaghan
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1 Answer

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\begin{gathered} (2x-8)/(2x^2+2x-40)=(2(x-4))/(2(x^2+x-20))=((x-4))/(x^2+x-20) \\ \text{Also} \\ x^2+x-20=(x+5)(x-4),\text{ then} \\ ((x-4))/(x^2+x-20)=((x-4))/((x+5)(x-4))=(1)/(x+5) \\ (2x-8)/(2x^2+2x-40)=(1)/(x+5) \end{gathered}

User Morwenn
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