Substituting x=y+1 in the first equation and solving for y we get:
[tex]\begin{gathered} -3(y+1)+4y=-1 \\ -3y-3+4y=-1 \\ y-3=-1 \\ y=-1+3 \\ y=2 \end{gathered}[/tex]Substituting y=2 in the second equation we get:
[tex]\begin{gathered} x=2+1 \\ x=3 \end{gathered}[/tex]Answer: x=3 and y=2.