We have to remember that in imaginary numbers or complex numbers we have that:
[tex]i^2=-1\Rightarrow i=\sqrt[]{-1}[/tex]Then, if we have:
[tex]\sqrt[]{-100}=\sqrt[]{100\cdot i^2}=i\cdot\sqrt[]{100}=i\cdot10=10i[/tex]Then, the answer to that square root is 10i.
