[tex]a).2x-5,3=0,78 \\ 2x=0,78+5,3 \\ 2x=6,08 \\ x= \frac{6,08}{2} \\ x=3,04 \\ b).12-(x-1)=2,4 \\ 12-x+1=2,4 \\ -x=2,4-12-1 \\ -x=-10,6 \\ x=10,6[/tex]
[tex]c).3,(2)+x\ \textless \ 9,(7) \\ \frac{29}{9} +x\ \textless \ \frac{88}{9} \\ x\ \textless \ \frac{88}{9} - \frac{29}{9} \\ x\ \textless \ \frac{59}{9} \\ x\ \textless \ 6,(5)[/tex]