Answer:
[tex]x=2i,\:x=-2i[/tex]
Step-by-step explanation:
[tex]x^2+9=5[/tex]
[tex]x^2+9-9=5-9[/tex]
[tex]x^2=-4[/tex]
[tex]x=\sqrt{-4},\:x=-\sqrt{-4}[/tex]