How do you solve $x^2+2x-7=17$ by completing the square?

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How do you solve $x^2+2x-7=17$ by completing the square?

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Answer 1 · 2015-05-15T14:14:33

Take $-7$ to the right:
$x^2+2x=17+7$
$x^2+2x=24$
add and subtract $1$ to the left:
$x^2+2x+1-1=24$
$(x^2+2x+1)-1=24$
$(x+1)^2-1=24$
$(x+1)^2=25$ take the square root of both sides and get rid of the $()^2$ :
$x+1=+-sqrt(25)$
$x=-1+-5$
So you get:
$x_1=-1+5=4$
$x_2=-1-5=-6$

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How do you solve $x^2+2x-7=17$ by completing the square?

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How do you solve x^2+2x-7=17x^2+2x-7=17 by completing the square?

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How do you solve $x^2+2x-7=17$ by completing the square?