\documentclass[a4paper, 12pt, openany,  oneside, arshad, Kashida, 	ABpages%
, ABfig, ABdiag ABgraph, ABalg, ABprog, ABtab
]{ABThesis}
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\begin{center} 
\nastaliq 
\begin{multicols}{2}
\begin{align}
-{\rm Maximize} Z^2_2=-x_1-3x_2\nonumber\hspace*{-1cm}\\
\hspace*{-2cm} s.t. \ 
1.5x_1+4.5x_2 &\leq  19.5&\nonumber\\
2x_1+5x_2 &\leq 20&\nonumber\\
2.5x_1+5.5x_2 &\leq 20.5&\nonumber\\
0.5x_1+2.5x_2 &\geq 2.5&\nonumber\\
x_1+3x_2 &\geq 3&\nonumber\\
1.5x_1+3.5x_2 &\geq 3.5&\\
2.5x_1+0.5x_2  &\leq 20.5&\nonumber\\
3x_1+x_2 &\leq 30&\nonumber\\
3.5x_1+1.5x_2 &\leq 30.5&\nonumber\\
\rightarrow 1.5x_1+0.5x_2&\geq 11&\nonumber\\
\rightarrow 2x_1+x_2 &\geq 15&\nonumber\\
\rightarrow 2.5x_1+1.5x_2 &\geq 19 &\nonumber\\
x_1,x_2&\geq 0&\nonumber\\
x^*_1=7.8 ,\quad x^*_2&=0& \nonumber\\
Z^{*2}_2=7.8
\nonumber
\end{align}
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\begin{align}
-{\rm Maximize} Z^2_1=-0.5x_1-2.5x_2 \nonumber\hspace*{-2cm}\\
 s.t. \ 
1.5x_1+4.5x_2 &\leq  19.5& \nonumber\hspace*{2cm}\\
2x_1+5x_2 &\leq 20& \nonumber\\
2.5x_1+5.5x_2 &\leq 20.5& \nonumber\\
0.5x_1+2.5x_2 &\geq 2.5& \nonumber\\
x_1+3x_2 &\geq 3&\nonumber\\
1.5x_1+3.5x_2 &\geq 3.5&\\
2.5x_1+0.5x_2  &\leq 20.5&\nonumber\\
3x_1+x_2 &\leq 30&\nonumber\\
3.5x_1+1.5x_2 &\leq 30.5 & \nonumber\\
\rightarrow 1.5x_1+0.5x_2&\geq 11& \nonumber\\
\rightarrow 2x_1+x_2 &\geq 15&\nonumber\\
\rightarrow 2.5x_1+1.5x_2 &\geq 19 &\nonumber\\
x_1,x_2&\geq 0&\nonumber\\
 x^*_1=7.8 ,\quad x^*_2&=0& \nonumber \\
 Z^{*2}_1=3.9
\nonumber
\end{align}
\end{multicols}
\end{center} 
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