In mathematics, the complex conjugate root theorem states that if P is a polynomial in one variable with real coefficients, and a + bi is a root of P with a and b real numbers, then its complex conjugate a − bi is also a root of P.
Here , one complex root is given -6i hence , the other must be 6i.
The correct answer is A. When dealing with an absolute value inequality, you want to flip the positive to a negative sign, as well as flip the inequality sign.