Equations

$$ \begin{equation} \begin{aligned} \frac{dx}{dt} &= \sigma (y - x) \\[5pt] \frac{dy}{dt} &= x (\rho - z) - y \\[5pt] \frac{dz}{dt} &= x y - \beta z \\ \end{aligned} \end{equation} $$

Source: wikipedia