Completing the square
[tex]x^2+18x=63[/tex][tex]\begin{gathered} x^2+18x+(\frac{18}{2})^2=63+(\frac{18}{2})^2 \\ x^2+18x+81=63+81 \\ x^2+18x+81=144 \\ (x+9)^2=144 \\ \end{gathered}[/tex][tex]\begin{gathered} (x+9)=\sqrt[]{144} \\ x+9=\pm12 \\ x_1=-12-9 \\ x_1=-21 \\ \\ x_2=12-9 \\ x_2=3 \end{gathered}[/tex]
The answer would be -21, 3
