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

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Answer 1 · 2017-05-14T14:52:59

The solution is $x=4 or x=-6$ .

We have:

$x^2+2x-7=17$

Adding 8 to both sides completes the square on the left.

$x^2+2x+1=25$

Completing squares gives:

$(x+1)^2=5^2$

Taking square roots gives:

$x+1=+-5$

This gives:

$x=4 or x=-6$

Answer 2 · 2017-05-14T14:53:36

${-6;4}$

$x^2+2x−7=17$

$=> x^2 +2x +1 = 25$
$=> (x+1)^2 = 25$
$=> x+1 = 5$ or $x+1 =-5$
$=> x = 4$ or $x = -6$

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