Answer:
[tex]\large\boxed{x=\pm5i}[/tex]
Step-by-step explanation:
[tex]i=\sqrt{-1}\to i^2=-1\\==========================\\\\x^2+25=0\qquad\text{subtract 25 from both sides}\\\\x^2=-25\to x=\pm\sqrt{-25}\\\\x=\pm\sqrt{(-1)(25)}\qquad\text{use}\ \sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\\\\x=\pm\sqrt{-1}\cdot\sqrt{25}\\\\x=\pm i\cdot5\\\\x=\pm5i[/tex]
