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4 votes
4 votes
Solve. (Enter answer as a command-separated list)
\sqrt[3]{2x {}^(2) + 9x - 47} = \sqrt[3]{x {}^(2) + 5x - 2}

User Madea
by
3.4k points

1 Answer

14 votes
14 votes

The Solution.

The given equation is


\sqrt[3]{2x^2+9x-47}=\text{ }\sqrt[3]{x^2+5x-2}

Raising both sides to the power of 3, we get


2x^2+9x-47=x^2+5x-2

Collecting the like terms, we get


\begin{gathered} 2x^2-x^2+9x-5x-47+2=0 \\ x^2+4x-45=0 \end{gathered}

Solving quadratically by factorization method, we get


\begin{gathered} x^2+9x-5x-45=0 \\ x(x+9)-5(x+9)=0 \\ (x+9)(x-5)=0 \end{gathered}

So,


\begin{gathered} x+9=0\text{ or x-5=0} \\ x=-9\text{ or x = 5} \end{gathered}

Therefore, the correct answer is 5 or -9

User Migonzalvar
by
2.8k points