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Questions: Algebra BusinessCalculus
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Factor \(\displaystyle 27 x^{3} + 21 x^{2} - 36 x - 28\).
Grouping the first two terms and factoring out their GCF, \(\displaystyle 3 x^{2}\), gives \(\displaystyle 3 x^{2}(9 x + 7)\). Grouping the last two terms and factoring out their GCF, \(\displaystyle -4\), gives \(\displaystyle -4(9 x + 7)\). The polynomial now has a common binomial factor of \(\displaystyle 9 x + 7\). This gives \(\displaystyle 3 x^{2} \left(9 x + 7\right) -4 \cdot \left(9 x + 7\right) = \left(9 x + 7\right) \left(3 x^{2} - 4\right)\).
\begin{question}Factor $27 x^{3} + 21 x^{2} - 36 x - 28$.
\soln{9cm}{Grouping the first two terms and factoring out their GCF, $3 x^{2}$, gives $3 x^{2}(9 x + 7)$. Grouping the last two terms and factoring out their GCF, $-4$, gives $-4(9 x + 7)$. The polynomial now has a common binomial factor of $9 x + 7$. This gives $3 x^{2} \left(9 x + 7\right) -4 \cdot \left(9 x + 7\right) = \left(9 x + 7\right) \left(3 x^{2} - 4\right)$. }
\end{question}
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\begin{document}\begin{question}(10pts) The question goes here!
\soln{9cm}{The solution goes here.}
\end{question}\end{document}<p> <p>Factor <img class="equation_image" title=" \displaystyle 27 x^{3} + 21 x^{2} - 36 x - 28 " src="/equation_images/%20%5Cdisplaystyle%2027%20x%5E%7B3%7D%20%2B%2021%20x%5E%7B2%7D%20-%2036%20x%20-%2028%20" alt="LaTeX: \displaystyle 27 x^{3} + 21 x^{2} - 36 x - 28 " data-equation-content=" \displaystyle 27 x^{3} + 21 x^{2} - 36 x - 28 " /> . </p> </p><p> <p>Grouping the first two terms and factoring out their GCF, <img class="equation_image" title=" \displaystyle 3 x^{2} " src="/equation_images/%20%5Cdisplaystyle%203%20x%5E%7B2%7D%20" alt="LaTeX: \displaystyle 3 x^{2} " data-equation-content=" \displaystyle 3 x^{2} " /> , gives <img class="equation_image" title=" \displaystyle 3 x^{2}(9 x + 7) " src="/equation_images/%20%5Cdisplaystyle%203%20x%5E%7B2%7D%289%20x%20%2B%207%29%20" alt="LaTeX: \displaystyle 3 x^{2}(9 x + 7) " data-equation-content=" \displaystyle 3 x^{2}(9 x + 7) " /> . Grouping the last two terms and factoring out their GCF, <img class="equation_image" title=" \displaystyle -4 " src="/equation_images/%20%5Cdisplaystyle%20-4%20" alt="LaTeX: \displaystyle -4 " data-equation-content=" \displaystyle -4 " /> , gives <img class="equation_image" title=" \displaystyle -4(9 x + 7) " src="/equation_images/%20%5Cdisplaystyle%20-4%289%20x%20%2B%207%29%20" alt="LaTeX: \displaystyle -4(9 x + 7) " data-equation-content=" \displaystyle -4(9 x + 7) " /> . The polynomial now has a common binomial factor of <img class="equation_image" title=" \displaystyle 9 x + 7 " src="/equation_images/%20%5Cdisplaystyle%209%20x%20%2B%207%20" alt="LaTeX: \displaystyle 9 x + 7 " data-equation-content=" \displaystyle 9 x + 7 " /> . This gives <img class="equation_image" title=" \displaystyle 3 x^{2} \left(9 x + 7\right) -4 \cdot \left(9 x + 7\right) = \left(9 x + 7\right) \left(3 x^{2} - 4\right) " src="/equation_images/%20%5Cdisplaystyle%203%20x%5E%7B2%7D%20%5Cleft%289%20x%20%2B%207%5Cright%29%20-4%20%5Ccdot%20%5Cleft%289%20x%20%2B%207%5Cright%29%20%3D%20%5Cleft%289%20x%20%2B%207%5Cright%29%20%5Cleft%283%20x%5E%7B2%7D%20-%204%5Cright%29%20" alt="LaTeX: \displaystyle 3 x^{2} \left(9 x + 7\right) -4 \cdot \left(9 x + 7\right) = \left(9 x + 7\right) \left(3 x^{2} - 4\right) " data-equation-content=" \displaystyle 3 x^{2} \left(9 x + 7\right) -4 \cdot \left(9 x + 7\right) = \left(9 x + 7\right) \left(3 x^{2} - 4\right) " /> . </p> </p>