the initial expression is:
[tex]y=3x+4[/tex]So this equation has already one solution
Now if we want to have infinit solution we an rest 3x so:
[tex]\begin{gathered} y=3x-3x+4 \\ y=4 \end{gathered}[/tex]So x can have any value, so there are infinit solutions
And to have no solutions we can add 5 -y at the left an