Since we have been introduced to complex numbers, we can take care of negative numbers under to square root.
The given square roots can be rewritten as
[tex]\sqrt{-2}=\sqrt{2}i[/tex]and
[tex]\sqrt{-18}=\sqrt{18}i=\sqrt{(2\cdot9)i}[/tex][tex](\sqrt{-18)}=3\sqrt{2i}[/tex]Therefore, the sum of these two numbers is
[tex]\sqrt{-2}+\sqrt{-18}=3(\sqrt{2i)+}\sqrt{2i}[/tex][tex]\textcolor{#FF7968}{=4\sqrt{2i}}[/tex]which is our answer.
