Solve the quadratic equation by completing the square. x²+18x+79=0

Mathematics

1 answer:

pogonyaev2 years ago

8 0

$x^2 + 18x=-79 \\ \\ x^2 + 18x+81=2 \\ \\ \boxed{(x+9)^2=2} \\ \\ x+9=\pm \sqrt 2 \\ \\ x=-9 \pm \sqrt{2} \\ \\ \boxed{x=-9+\sqrt{2}, -9-\sqrt{2}}$

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