Answer:
[tex]\textbf{A. }x=2i\text{ or }x=-2i\\\\\textbf{B. }(x+2i)(x-2i)[/tex]
Step-by-step explanation:
The quadratic can be solved in a straightforward way:
[tex]x^2+4=0\\\\x^2=-4\qquad\text{subtract 4}\\\\x=\pm\sqrt{-4}\qquad\text{take the square root}\\\\x=\pm2i\qquad\text{simplify}[/tex]
This tells you that the solutions are ...
2i or -2i
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For each root of "a", (x -a) is a factor. Thus the factors of the equation are ...
(x +2i)(x -2i)