# Boxed equations and arrows

I would like to implement this into an align-environment (or equivalent) how can I do this? I tried with boxes but the structure is rather complicated since I want a large box on the left-hand side....

Here you go. I could not replicate the font other than using a Sans Serif family (it appears bold in mine).

## Code

\documentclass[margin=10pt]{standalone}
\usepackage{tikz}

\usetikzlibrary{arrows.meta,calc,positioning}

\tikzset{
every node/.style={draw=gray, rounded corners, text centered,text width=3cm},
}

\begin{document}
\begin{tikzpicture}[
>=latex,
font=\sffamily
]
\node[minimum height=4cm,minimum width=3cm] (big) at (0,0) {text\\more text};

\node[font=\Large\sffamily, right=of big.north east, anchor=north west,minimum height=1cm] (s1) {equation};
\node[right=of big.south east, anchor=south west,minimum height=1cm] (s2) {a lot of text\\and another line};

\node[draw=none] at ($(big.north east)!.5!(s1.south west)$) {$\times$};
\node[draw=none] at ($(big.south east)!.5!(s2.north west)$) {$\times$};

\draw[<->, shorten >=5mm, shorten <=5mm] (s1.south) -- (s2.north);

\end{tikzpicture}
\end{document}

• Instead of X, may be $\times$? – Manuel May 16 '15 at 12:32
• @Manuel Although in the question there are 2 Xs, that looks better (and probably the OP meant that symbol anyway). I'll change it. – Alenanno May 16 '15 at 14:08