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simplify to create an equivalent expression6(5r-11)-(5-r)my answer is 29r-71correct answer is 31r-71 how is it 31r when the r is negative and 30r is positive

User Ingulit
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1 Answer

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We want to simplify the expression;


\begin{gathered} 6(5r-11)-1(5-r) \\ \text{Let's open the brackets, we would have} \\ 30r-66-5+r \\ \text{collect like terms to obtain} \\ 31r-71 \end{gathered}

So, the mistake you made is to forget to multiply the negative r by -1 when expanding.

- 1 x - r = + r

The equivalent expression is ,therefore , 31r - 71

User Stuart Douglas
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