Answer:
√10
Step-by-step explanation:
There are a couple of ways you can go at this.
[tex]\dfrac{\sqrt{-40}}{\sqrt{-4}}=\sqrt{\dfrac{-40}{-4}}=\boxed{\sqrt{10}}[/tex]
or ...
[tex]\dfrac{\sqrt{-40}}{\sqrt{-4}}=\dfrac{2\sqrt{10}\,i}{2\,i}=\boxed{\sqrt{10}}[/tex]
