\begin{equation}10(x+y)\end{equation}

\begin{equation}x(6+y)\end{equation}

\begin{equation}(x+y) \times 6\end{equation}

\begin{equation}2(7x+8)\end{equation}

\begin{equation}3(x+y+z)\end{equation}

\begin{equation}8x+8y\end{equation}

\begin{equation}8x+40y\end{equation}

\begin{equation}x+x\end{equation}

\begin{equation}9x+7x\end{equation}

\begin{equation}6x+8y+5x+4y\end{equation}

\begin{equation}8x^{9}+2x^{9}\end{equation}