If a polynomial has one root in the form a + the square root of b it has a second root in the form of a _ square root of b.

Step-by-step explanation:

It's important to know that where roots of a polynomial involves radical roots, it does as conjugates. That is, the roots have the same terms but with a opposite middle sign between.

So, in this case, we have one root , which involves a root and a positive sign. To complete the conjugate behaviour, the other roots has to have the same terms but with different sign between, that is

Therefore, the answer that completes the given statement is

then

answer is a. 13.268 l know it is