# Align two sets of two column equations and number one set

In got some great help in the related posts:

I would like to align both equations sets and be able to have text between both. I figured out how to achieve this with intertext. Could you help me to find a way to number only the top five equations and have the number centered on the right side of those five equations? Here is my MWE:

    \documentclass[12pt]{scrreprt}
\usepackage[a4paper, includehead, left=3.5cm, right=1.7cm, top=2.5cm, bottom=2.0cm]{geometry}

\usepackage[no-math]{fontspec}
\setmainfont{Arial}

\usepackage[ngerman]{babel}
\usepackage{array,booktabs,amsmath}

\usepackage[]{siunitx}
\sisetup{locale = DE,group-separator={.}}
\sisetup{per-mode=symbol}
\sisetup{detect-all}

\begin{document}

\begin{align*}
t_a  & =  \frac{v}{a} & h_a & =  \frac{1}{2} \times a \times {t_a}^2 \\
h_v & =  h_t - h_a - h_r & t_v & =  \frac{h_v}{v} \\
t_t & =  2 \times (t_a + t_v + t_r + t_d) & &
\intertext{Some Text}
t_a & = \frac{\SI{6}{\metre\per\second}}{\SI{0,6}{\metre\per\second\squared}} & h_a & = \frac{1}{2} \times \SI{6}{\metre\per\second\squared} \times {\SI{10}{s}}² \\
& = \SI{10}{s} & & = \SI{30}{m} \\[1ex]
t_v & = \frac{\SI{240}{m}}{\SI{6}{\metre\per\second}} & h_v & = \SI{300}{m} - \SI{30}{m} - \SI{30}{m} \\
& = \SI{40}{s} & & = \SI{240}{m} \\[1ex]
t_t & = 2 \times (\SI{10}{s} + \SI{40}{s} + \SI{8}{s} + \SI{120}{s}) \\
& = \SI{356}{s}
\end{align*}

\end{document}


Use align with \nonumber in each line except the second one.

\documentclass[12pt]{scrreprt}
\usepackage[a4paper, includehead, left=3.5cm, right=1.7cm, top=2.5cm, bottom=2.0cm]{geometry}

\usepackage[no-math]{fontspec}
\setmainfont{Arial}

\usepackage[ngerman]{babel}
\usepackage{array,booktabs,amsmath}

\usepackage[]{siunitx}
\sisetup{locale=DE,group-separator={.}}
\sisetup{per-mode=symbol}
\sisetup{detect-all}

\begin{document}

\begin{align}
t_a & =  \frac{v}{a} & h_a & =  \frac{1}{2} \times a \times {t_a}^2\nonumber \\
h_v & =  h_t - h_a - h_r & t_v & =  \frac{h_v}{v} \\
t_t & =  2 \times (t_a + t_v + t_r + t_d) & &  \nonumber
\intertext{Some Text}
t_a & = \frac{\SI{6}{\metre\per\second}}{\SI{0,6}{\metre\per\second\squared}} & h_a & = \frac{1}{2} \times \SI{6}{\metre\per\second\squared} \times {\SI{10}{s}}² \nonumber\\
& = \SI{10}{s} & & = \SI{30}{m} \nonumber\\[1ex]
t_v & = \frac{\SI{240}{m}}{\SI{6}{\metre\per\second}} & h_v & = \SI{300}{m} - \SI{30}{m} - \SI{30}{m} \nonumber\\
& = \SI{40}{s} & & = \SI{240}{m} \nonumber\\[1ex]
t_t & = 2 \times (\SI{10}{s} + \SI{40}{s} + \SI{8}{s} + \SI{120}{s}) \nonumber\\
& = \SI{356}{s} \nonumber
\end{align}

\end{document} 