TeX source:

\begin{aligned} &\Delta x_{1}+\Delta x_{2}+\Delta x_{3}+\ldots+\Delta x_{n}=\left(x_{1}-x_{0}\right)+\left(x_{2}-x_{1}\right)+\left(x_{3}-x_{2}\right)+\ldots+\left(x_{n}-\right. \\ &\left.x_{n-1}\right)=x_{n}-x_{0} \end{aligned}