Alright that does sound easy, didn't know there was such thing we can do and it makes it a lot easier to deal with. Thanks a lot.
Now I have to solve them with simultaneous equations and I got the feeling that it's really going to look nasty and impossible to solve, is there a better way to do it ?
Suggestions to "make the process" less unwieldy:
Change V1 to u and V2 to v.
Let a=2200, b=5600, c=3300, d=6800 (the 4 denominators).
Equations become:
(u-22)/a + (u+12)/b + (u-v)/c = 0 [1]
(v-6)/d + (v-u)/c = 0 [2]
Solve [2] for v, substitute in [1]
TIP: if a fraction = 0, then numerator = 0