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use factoring to find the following quotient n^2-15n+56÷n-8 a)n-7 b) n-10+ 2/n-8 c)n-5+ 2/n-8 d) n-7+ 5/n-8

1 Answer

2 votes

(n^2-15n+56)/(n-8)

Factoring the numerator


n^2-15n+56=0

use the formula


n=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a}

and replace


\begin{gathered} n=\frac{-(-15)\pm\sqrt[]{(-15)^2-4(1)(56)}}{2(1)} \\ \\ n=\frac{15\pm\sqrt[]{1}}{2} \\ \\ n=(15\pm1)/(2) \\ \\ n_1=(15+1)/(2)=8 \\ \\ n_2=(15-1)/(2)=7 \end{gathered}

the factored expression is


(n-8)(n-7)

now replacing on the first expression


((n-8)(n-7))/((n-8))

we can simplify (n-8),so


((n-8)(n-7))/((n-8))\longrightarrow(n-7)

so, the right option is A

User Kornelius
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