To solve the equation \( 7x^9 + 4x^2\sqrt{12} + 4 = 2 \), the first step should typically be to isolate terms involving \(x\).
Out of the given options, Option #3: Subtract 4 from both sides of the equation. is the most appropriate first step. This action simplifies the equation by eliminating the constant on the left side, making it easier to work with.
So the answer is:
Option #3.