Question

Quadratic equation by completing the square x^2+6x=18

Answer 1

$x^2+6x=18\\ x^2+6x+9=27\\ (x+3)^2=27\\ x+3=\sqrt{27} \vee x+3=-\sqrt{27}\\ x=-3+3\sqrt 3 \vee x=-3-3\sqrt3$