The op amp will likely go to full voltage on either power supply rail, so it depends on the component being used. Very few op amps anywhere near the power supply rails. You don't have a component for the op amp, you don't have power supply definitions. In short, as stated the question is unanswerable.
Find V- (inverting input voltage with respect to ground) and V+ (non inverting input voltage with respect to ground). Then equate V- and V+ (ideal op amp) and you should find Vo with respect to Vin.
V+=(Vo*12k)/(12k+8k)=0.6*Vo , voltage divider rule current through 4k and 16k is: assume current flows from Vo to 6V I=(Vo-6)/(4+16)k=(Vo-6)/20k thus V-=6+I*4k=6+4k(Vo-6)/20k=6+(Vo-6)*0.2=6+0.2*Vo-1.2=0.2*Vo+4.8 assuming V-=V+ 0.6*Vo=0.2*Vo+4.8 thus 0.4*Vo=4.8 thus Vo=12V Io=12V/10k=1.2mA
Millman's Theorem Solution....... **************************************** **************************************** hgmjr