Question

use the complex conjugate root theorem to state another complex solution. given that -7i is a root. 7i; -7i+1; 1+7i; 1-7i

Explanation:

Step1: Recall Complex Conjugate Theorem

For polynomials with real coefficients, if $a+bi$ is a root, its conjugate $a-bi$ is also a root.

Step2: Identify conjugate of $-7i$

Given root is $0 - 7i$, so its conjugate is $0 + 7i = 7i$.

Answer:

A. $7i$