209k views
2 votes
Some the quadratic equation by completing the square.x^2+4x-11=0First choose the appropriate form and fill in the blanks with the correct numbers. Then solve the equation. If there’s more than one solution separate them with commas.

Some the quadratic equation by completing the square.x^2+4x-11=0First choose the appropriate-example-1

1 Answer

3 votes

x^2+4x-11=0

By completing the square, we have:


\begin{gathered} x^2+4x=11 \\ x^2+4x+2^2=11+2^2 \\ (x+2)^2=11+4 \\ (x+2)^2=15 \end{gathered}

Take the square root of both sides


\begin{gathered} (x+2)=\pm\sqrt[]{15} \\ x=+\sqrt[]{15}-2\text{ OR x= -}\sqrt[]{15}-2 \\ x=3.8729-2\text{ OR -3.8729-2} \\ x=1.873\text{ OR -5.873} \end{gathered}

User Joel G Mathew
by
2.9k points