When x is -3
[tex]3\left(-3\right)-7y=13\quad :\quad y=-\frac{22}{7}\quad \left(\mathrm{Decimal}:\quad y=-3.14285\dots \right)[/tex]
When x is 0
[tex]3\cdot \:0-7y=13\quad :\quad y=-\frac{13}{7}\quad \left(\mathrm{Decimal}:\quad y=-1.85714\dots \right)[/tex]
When x is 3
[tex]3\cdot \:3-7y=13\quad :\quad y=-\frac{4}{7}\quad \left(\mathrm{Decimal}:\quad y=-0.57142\dots \right)[/tex]
