Habe die Befehle \begin{align} sowie \begin{aligned} sowie \begin{split} scho ausprobiert. Hier ist mein Latex-Dokument:
\documentclass[bibliography=totoc,12pt]{scrartcl}
\usepackage[ngerman]{babel}
\usepackage{amsmath}
\usepackage{color}
\usepackage{amsthm}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{tikz}
\usepackage{here}
\usepackage{colortbl}
\usepackage[titletoc]{appendix}
\usepackage[authoryear]{natbib}
\usepackage[a4paper,left=3cm,right=2cm,top=2cm,bottom=2cm]{geometry}
\usepackage{pgfplots}
\usepackage{eurosym}
\usepackage[justification=RaggedRight, singlelinecheck=false]{caption}
\usepackage{tocstyle}
\usepackage[nottoc, numbib,]{tocbibind}
\usepackage{mathtools}
\pgfplotsset{
compat=1.9,
xlabel near ticks,
ylabel near ticks}
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhf{}
\fancyhead[L]{}
\fancyhead[R]{}
\fancyfoot[R]{}
% Umdefinition pagestyle plain
\fancypagestyle{plain}
\fancyhf{}
\fancyfoot[R]{\thepage}
\renewcommand{\headrulewidth}{0pt}
\renewcommand{\footrulewidth}{0pt}
\usepackage{setspace}
\onehalfspacing
\newcommand{\bs}{\verb|\|}
\newtheorem{assumption}{Assumption}
\newtheorem{proposition}{Proposition}
\newtheorem{corollary}{Corollary}
\newtheorem{definition}{Definition}
\newtheorem{theorem}{Theorem}
\newtheorem{hypothesis}{Hypothesis}
\newtheorem{algorithm}{Algorithm}
\bibliographystyle{authordate1}
\date{}
\usepackage[utf8]{inputenc}
\setcounter{secnumdepth}{4}
\setkomafont {disposition}{\normalfont\bfseries}
\begin{document}
\begin{equation*}
s.d.\qquad C_{At}^S+p_{Bt}C_{Bt}^S+q_t^h\Bigl[(1-\tau_h)(1+VAT)(H_t^S-(1-\delta)H_{t-1}^S+(H_t^Z-(1-\delta)H_{t-1}^Z)\Bigl]+b_t+d_t=(1-\tau_{wt})(w_{ct}L_{ct}^S+w_{ht}L_{ht}^S)+q_t^ZA_ZH_t^Z+\frac{R_{At-1}B_{t-1}}{\pi}+\frac{R{t-1}e^{\psi\frac{-d_{t-1}}{Y_{t-1}d{t-1}}}{\pi_{At}}+F_t
\end{equation*}
\end{document}
