Simplify \(\sqrt{-9}\) to \(\sqrt{9}\imath \).
\[6{\imath }^{2}-\sqrt{9}\imath \]
Since \(3\times 3=9\), the square root of \(9\) is \(3\).
\[6{\imath }^{2}-3\imath \]
Use Square Rule: \({i}^{2}=-1\).
\[6\times -1-3\imath \]
Simplify \(6\times -1\) to \(-6\).
\[-6-3\imath \]
-6-3*IM
