How do you solve $x^2 + 6x + 2 = 0$ by completing the square?

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Answer 1 · 2015-04-01T22:53:33

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$x^2+6x+2=0$

$(x^2+6x color(white)"ssssssss")+2=0$

$1/2 * 6 = 3$ . and $3^2 = 9$ so we need to add $9$ to get a complete square:

$(x^2+6x +9-9)+2=0$

$(x^2+6x +9)-9+2=0$

$(x+3)^2-7=0$

$(x+3)^2=7$

$x+3= +-sqrt7$

$x= -3 +-sqrt7$

The solutions are: $-3 -sqrt7$ , $-3 +sqrt7$

How do you solve x^2 + 6x + 2 = 0x^2 + 6x + 2 = 0 by completing the square?