I used an aligned subequations environment, but for some reason my equations are aligned at the right side of the paper and falling off. I want them to be centered, and aligned at the = sign, with the equation number not below but at the right side of the equation. This is my code:
\documentclass{report}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{geometry}
\geometry{a4paper}
\usepackage{mathtools}
\usepackage{graphicx}
\usepackage{booktabs}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{tikz} %for simple drawings and diagram
\usetikzlibrary{fit,shapes.geometric}
\usetikzlibrary{arrows}
\usetikzlibrary{shapes}
\usepackage{pgfplots}
\usepackage{caption}
\usepackage{subcaption}
%page numbering abstract
\usepackage{etoolbox}
\patchcmd{\abstract}{\titlepage}{\clearpage}{}{}
\patchcmd{\andabstract}{\endtitlepage}{\clearpage}{}{}
%for bibliography
\usepackage{natbib}
\bibliographystyle{apa}
%Includes "References" in the table of contents
\usepackage[nottoc]{tocbibind}
%to use subsections
\usepackage{titlesec}
\titleformat{\chapter}[hang]
{\normalfont\huge\bfseries}
{\thechapter}{20pt}{\huge}
\begin{document}
\chapter{Results}
\section{Elasticity analysis}
\begin{subequations} \allowdisplaybreaks
\begin{align}
\frac{\partial \lambda}{\partial q_{T,1}}&=\frac{q_{T,2}n_Tf_T(1-v)\lambda^3-q_{T,2}n_Tf_T(1-v)(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial q_{T,2}}&=\frac{q_{T,1}n_Tf_T(1-v)\lambda^3-q_{T,1}n_Tf_T(1-v)(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial q_{L,1}}&=\frac{q_{L,2}n_Lf_L\lambda^3-q_{L,2}n_Lf_L(q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{T,2}s_{T,1})2\lambda}{denominator} \
\frac{\partial \lambda}{\partial q_{L,2}}&=\frac{q_{L,1}n_Lf_L\lambda^3-q_{L,1}n_Lf_L(q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{T,2}s_{T,1})2\lambda}{denominator} \
\frac{\partial \lambda}{\partial a_{T,1}}&=\frac{s_{T,2}\lambda^3-s_{T,2}(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1}\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial s_{T,2}}&=\frac{s_{T,1}\lambda^3-s_{T,1}(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1}\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial s_{L,1}}&=\frac{s_{L,2}\lambda^3-(s_{L,2}q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{L,2}s_{T,2}s_{T,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial s_{L,2}}&=\frac{s_{L,1}\lambda^3-(s_{L,1}q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{L,2}s_{T,2}s_{T,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial n_T}&=\frac{q_{T,2}q_{T,1}f_T(1-v)\lambda^3-q_{T,2}q_{T,1}f_T(1-v)(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial f_T}&=\frac{q_{T,2}q_{T,1}n_T(1-v)\lambda^3-q_{T,2}q_{T,1}n_T(1-v)(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial n_L}&=\frac{q_{L,2}q_{L,1}f_L\lambda^3-q_{L,2}q_{L,1}f_L(q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{T,2}s_{T,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial f_L}&=\frac{q_{L,2}q_{L,1}n_L\lambda^3-q_{L,2}q_{L,1}n_L(q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{T,2}s_{T,1})\lambda^2}{denominator} \
\frac{\partial \lambda}{\partial v}&=\frac{-q_{T,2}q_{T,1}n_Tf_T\lambda^3+q_{T,2}q_{T,1}n_Tf_T(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1}\lambda^2}{denominator} \
\text{with }
denominator=4\lambda^3-(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1}+q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{T,2}s_{T,1})3\lambda^2 \
+(q_{L,2}q_{L,1}n_Lf_L+s_{L,2}s_{L,1})(q_{T,2}q_{T,1}n_Tf_T(1-v)+s_{T,2}s_{T,1})2\lambda
\end{align}
\end{subequations}

=. In your case the last line (from\text{width }does not contain a&and therefore is at whole the left part of analignrow. So you should at least add a&afterdenominator(which should be\mathrm{denominator}or\mathit{denominator}or even\text{denominator}and also before the*in the last line. Instead of\text{with }I would also suggest\intertext{with }. Alternatively use a separate environment, e.g.,gatherorsplit. – cabohah Mar 01 '23 at 11:31\text{with}to\intertext{with}and (b) add suitable alignment points in the final two rows. – Mico Mar 01 '23 at 11:40