I don't want to tell you the full answer, but I'll start you off.
Multiply both sides by x and get \(\sqrt{1-4x^2}-1 \geq -4x\).
To get rid of the radical, we can move all radical signs to the left and non-radicals to the right.
This is what we'll do here.
\(\sqrt{1-4x^2} \geq -4x+1\).
Now square both sides, and then you probably know what to do from there.
You are very welcome!
:P
