\[\begin{array}{*{35}{l}}
\left( 1\text{ }-\text{ }i \right)-\text{ }\text{ }\left( \text{ }1\text{ }+\text{ }i6 \right)\text{ }=\text{ }1\text{ }-\text{ }i\text{ }+\text{ }1\text{ }-\text{ }i6 \\
=\text{ }2\text{ }-\text{ }i7 \\
\end{array}\]
Henceforth,
\[\left( 1\text{ }-\text{ }i \right)\text{ }-\text{ }\left( -\text{ }1\text{ }+\text{ }i6 \right)\text{ }=\text{ }2\text{ }-\text{ }i7\]