Subtract 121 from both sides:
[tex]25x^2=-121[/tex]
Divide both sides by 25:
[tex]x^2 = -\dfrac{121}{25}[/tex]
The solutions would be
[tex]x = \pm\sqrt{-\dfrac{121}{25}}[/tex]
This expression cannot be evaluated using real numbers, because the square root of negative numbers are not allowed. If we're using complex numbers, the solutions are
[tex]x = \pm\sqrt{-\dfrac{121}{25}} = \pm\dfrac{11i}{5}[/tex]
