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Please help if you can I’m not understanding this I appreciate it thank you so much

Please help if you can I’m not understanding this I appreciate it thank you so much-example-1

1 Answer

6 votes

ANSWER


B)\text{ }x=\frac{1\pm2\sqrt[]{3}}{3}

Step-by-step explanation

To solve this, first, we have to subtract 11 from both sides of the equation,


\begin{gathered} 9x^2-6x-11=11-11 \\ \\ 9x^2-6x-11=0 \end{gathered}

Now, the equation is in the form,


ax^2+bx+c=0

And we can apply the quadratic formula,


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

In this case, a = 9, b = -6, and c = -11,


x=\frac{-(-6)\pm\sqrt[]{(-6)^2-4\cdot9\cdot(-11)}}{2\cdot9}=\frac{6\pm\sqrt[]{36+396}}{18}=\frac{6\pm\sqrt[]{432}}{18}=\frac{6\pm12\sqrt[]{3}}{18}

We can simplify this by factoring out 6 in both the numerator and denominator,


x=\frac{6((6)/(6)\pm(12)/(6)\sqrt[]{3})}{6((18)/(6))}=\frac{1\pm2\sqrt[]{3}}{3}

Hence, the answer is option B.

User Julien Leray
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