## sonja_lee2 Group Title complete the square. x^2+2x=9 explain... one year ago one year ago

take half of 2, which is 1, and write $(x+1)^2=9+1^2=10$
now that you have $(x+1)^2=10$ to solve take the square root and get $x+1=\pm\sqrt{10}$ so $x=-1\pm\sqrt{10}$