I have been searching for a solution, but most modify all rows, or use a different packages. I would like to only add padding where the numbers are touching the horizontal lines, without modifying the other rows.
\documentclass[12pt, a4paper]{report}
\usepackage[top=3cm,bottom=2.5cm,right=2.5cm,left=4cm]{geometry}
\usepackage{array}
\usepackage{amsmath}
\usepackage{multirow}
\usepackage{graphicx}
\usepackage{times}
\begin{document}
\begin{table}[h]
\centering
\small
% \renewcommand\cellalign{bc}
\setlength\tabcolsep{5pt}
\begin{tabular}{c|c|c|c|c|c|c|c|l}
\hline
\multirow{2}{2.5em}{\textbf{Var. basica}}
& \multirow{2}{*}{\textbf{ Eq.}}
& \multicolumn{6}{c|}{\textbf{Coeficiente}}
& \multirow{2}{*}{\textbf{Lado der.}} \\
\cline{3-8}
& &
$Z$ & $x_1$ & $x_2$ & $x_3$ & $x_4$ & $x_5$ \\
\hline
$Z$ & $(0)$ & $1$ & $-180$ & $-90$ & $0$ & $0$ & $0$ & $0$ \\
\hline
$x_3$ & $(1)$ & $0$ & $6$ & $8$ & $1$ & $0$ & $0$ & $48 \to \dfrac{48}{ 6} = 8 $ \\
\hline
$x_4$ & $(2)$ & $0$ & $1$ & $0$ & $0$ & $1$ & $0$ & $6 \to \dfrac{6}{1} = 6 \leftarrow min$ \\
\hline
$x_5$ & $(3)$ & $0$ & $0$ & $1$ & $1$ & $1$ & $1$ & $4$ \\
\hline
\end{tabular}
\caption{Aplicacion de la prueba de proporcion minima}
\label{tab:simplex_tabular_1}
\end{table}
\end{document}
\dfrac
not\frac
? alsomin
should be\mathrm{min}
but\rule[xxx]{0pt}{yyy}
will allow you to force any amount of spacetabularray
package for writing of tables) in my answer to your previous question (tex.stackexchange.com/questions/686961/…), than you would have desired behaviours of rows.tabularray
along other table doesn't make any conflict with other tables' packages. You have problems with some other consistency in your document. Since it is not known, to me I can't advice how to manage with them.