How Do You Solve Complex MOSFET Equations in Homework Problems?

[CoolDude420]

Homework Statement

Homework Equations

The Attempt at a Solution

I think that up there is right so far since I didn't see any other relationship between the two MOSFETS other than their IDs are equal. But after I keep simplifying that equality, I end up with this

I have no idea what to do with this now.

 

[NascentOxygen]

I haven't tried this, but if you could solve one of your I_D equations for V_A, then substitute that for V_A in the other, you'd have the I–V relation for the combination without involving V_A.