[tex]35*5-54:a*4=139=\ \textgreater \ \\
175- \frac{54}{a}*4=139=\ \textgreater \ \\
175- \frac{216}{a} =139, a \neq 0=\ \textgreater \ \\
- \frac{216}{a} =139-175=\ \textgreater \ \\
- \frac{216}{a} =-36 =\ \textgreater \ \\
-216=-36a=\ \textgreater \ \\
-36a=-216=\ \textgreater \ \\
a=6, a \neq 0=\ \textgreater \ \\
S=[6] \\
Succes
[/tex]
