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I need help with this please 4x^2 - 18 = 82

User Issathink
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1 Answer

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Given the following equation:


4x^2-18=82

if we add 18 on both sides, we get:


\begin{gathered} 4x^2-18+18=82+18 \\ \Rightarrow4x^2=100 \end{gathered}

next, we can divide both sides by 4 to get the following:


\begin{gathered} (4x^2=100)((1)/(4)) \\ \Rightarrow(4)/(4)x^2=(100)/(4) \\ \Rightarrow x^2=25 \end{gathered}

finally, we can apply the square root on both sides of the equation to find the values of x:


\begin{gathered} \sqrt[]{x^2}=\sqrt[]{25} \\ \Rightarrow x=\pm5 \end{gathered}

therefore, x = 5 and x = -5

User Skjalg
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