Given
[tex]16x+9=9y-2x[/tex]You have to solve it for y, so first step is to have one side of the equation with the term associated iwth y and all other terms in the other side.
[tex]\begin{gathered} 16x+9+2x=9y-2x+2x \\ 16x+2x+9=9y \\ 9y=18x+9 \end{gathered}[/tex]Next divide by 9 both sides to reach the equivalency for y:
[tex]\begin{gathered} \frac{9y}{9}=\frac{18x+9}{9} \\ \frac{9}{9}y=\frac{18x}{9}+\frac{9}{9} \\ y=2x+1 \end{gathered}[/tex]