I have this system:

And I have to find the intersecting points of the two equations by using substitution and only substitution.

I solved the bottom equation for y getting . From there, this is how I progressed:

Combining like terms:

Pulling out a 3 gives me:

From here, I'm not sure what to do. Am I on the right track or am I doing this completely wrong? If the latter, please explain to me where I made an error so it doesn't happen again.

Thank you.