Sum of radical sign -2 and radical sign -18

Answer:
B
Step-by-step explanation:
Note that [tex]\sqrt{-1}[/tex] = i
[tex]\sqrt{-2}[/tex] = [tex]\sqrt{2(-1)}[/tex] = [tex]\sqrt{2}[/tex] i
[tex]\sqrt{-18}[/tex] = [tex]\sqrt{9(2)(-1)}[/tex] = 3[tex]\sqrt{2}[/tex] i
Thus the sum is
[tex]\sqrt{2}[/tex] i + 3[tex]\sqrt{2}[/tex] i = 4[tex]\sqrt{2}[/tex] i → B