7. Let $u$ and $v$ be functions of $x$ that are differentable at $x=-11$. Given that $u(-11)=-6, w(-11)=7, v(-11)=-5$, and $v(-11)=-4$, find the value of the following derivative at \[ \begin{array}{l} x=-11 \text {. } \\ \frac{d}{\dx}(u-6 v)=\text {. }