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Complete the square to write the quadratic equation in vertex form: x^2+4x-5=0

Complete the square to write the quadratic equation in vertex form: x^2+4x-5=0-example-1
User Swordray
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1 Answer

21 votes
21 votes

Let's solve the equation:


\begin{gathered} x^2+4x-5=0 \\ x^2+4x=5 \\ x^2+4x+((4)/(2))^2=5+((4)/(2))^2 \\ (x+2)^2=5+(16)/(4) \\ (x+2)^2=(36)/(4) \\ x+2=\pm\sqrt[]{(36)/(4)} \\ x+2=\pm3 \\ \text{ then} \\ x=-2+3 \\ x=1 \\ or\text{ } \\ x=-2-3 \\ x=-5 \end{gathered}

Therefore, the solutions of the equation are x=1 and x=-5

User Shreyansh Panchal
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