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Solve the equation 4x2 + 8x + 1 = 0 by completing the square. Verify your answer using the quadratic formula.

Solve the equation 4x2 + 8x + 1 = 0 by completing the square. Verify your answer using-example-1

1 Answer

4 votes

Given:


4x^2+8x+1=0


\begin{gathered} x^2+2x+(1)/(4)=0 \\ x^2+2x+1-1+(1)/(4)=0 \\ (x+1)^2=1-(1)/(4) \\ (x+1)^2=(3)/(4) \end{gathered}

Taking square root on both sides


\begin{gathered} x+1=\pm\frac{\sqrt[]{3}}{2} \\ x=-1\pm\frac{\sqrt[]{3}}{2} \\ x=\frac{-2\pm\sqrt[]{3}}{2} \end{gathered}

3rd option is the final answer

User Oleg Kuts
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