\frac{dx_{1}}{dt} = \left(1 \cdot k_{9} \cdot k_{1} \cdot x_{3} + 1 \cdot k_{9} \cdot k_{2} \cdot k_{10} + -1 \cdot k_{9} \cdot k_{3} \cdot x_{1}\right) / k_{9}\\
\frac{dx_{2}}{dt} = 0