[tex]\bf \begin{cases} \boxed{y}=\log(2x+1)\\ y=3x-2 \end{cases}\qquad \stackrel{\textit{doing substitution on the 2nd equation}}{\boxed{\log(2x+1)}=3x-2}[/tex]
a quick note, I must say that writing y₁ and y₂ is a bit misleading, since it makes it appear as if they're two different variables, when they're the same one.
