[tex]X + y = 12[/tex]
[tex]3x = 2y + 6[/tex]
In the first equation, multiply the first equation by 2.
In the second equation, move the 2y to the left.
[tex]2x+2y=24[/tex]
[tex]3x-2y=6[/tex]
Add the two equations to eliminate y and solve for x:
[tex]5x+0=30[/tex]
[tex]x=6[/tex]
Plug-in the the value of x in the either original equation to solve for x.
I will use the first original equation because it is simpler than the second.
[tex]X + y = 12[/tex]
[tex]y=6;x=6[/tex]