Answer:
x = ± 6i
Step-by-step explanation:
Given
2x² + 72 = 0 ( subtract 72 from both sides )
2x² = - 72 ( divide both sides by 2 )
x² = - 36 ( take the square root of both sides )
x = ± [tex]\sqrt{-36}[/tex]
= ±( [tex]\sqrt{36(-1)}[/tex])
= ±( [tex]\sqrt{36}[/tex] × [tex]\sqrt{-1}[/tex]) → [tex]\sqrt{-1}[/tex] = i
= ± 6i
