Answer: [tex]x = \frac{2}{3}i , -\frac{2}{3}i[/tex]
Step-by-step explanation:
9x² + 4 = 0
-4 -4
9x² = -4
[tex]\frac{9x^{2} }{9} = \frac{-4}{9}[/tex]
x² = [tex]\frac{-4}{9}[/tex]
[tex]\sqrt{x^{2} } = \sqrt{-\frac{4}{9} }[/tex]
[tex]x = +/- \frac{2}{3}i[/tex]