[tex]a=\frac{3}{10},\text{ x=}\frac{-3}{20}[/tex][tex]\begin{gathered} \text{Thus, 4x-a=4(}\frac{-3}{20})-\frac{3}{10} \\ \frac{-12}{20}-\frac{3}{10} \end{gathered}[/tex][tex]\begin{gathered} \frac{-12-6}{20} \\ \frac{-18}{20} \\ \frac{-9}{10} \end{gathered}[/tex]
