we already have the slope so in this case we can use the equation of the slope and replace its values, ane coordinate (2,5) and replace x=0 so:
[tex]\begin{gathered} m=\frac{y-y_1}{x-x_1} \\ 3=\frac{y-5}{0-2} \end{gathered}[/tex]and we solve for y so:
[tex]\begin{gathered} -2\cdot3=y-5 \\ -6+5=y \\ -1=y \end{gathered}[/tex]So the equation is:
[tex]y=3x-1[/tex]