Question is, find voltage at point B.
Total voltage 12 V - 9 V = 3 Volts
Total resistance = (47+27+56+20)10^3 = 150000 Ohms
Circuit current = V/R = 3/150000 = 0.00002 Amps
I can go 2 directions:
R2, R1, and 9 V back to ground
OR
R3, R4, 12 V back to ground.
R2+R1 = 74000 Ohms * 0.00002 Amps = 1.48 Volts
R3 + R4 = 76000 Ohms * 0.00002 Amps = 1.52 Volts
9 - 1.48 = 7.52 Volts
12 - 1.52 = 10.48 Volts
From my understanding it should be add voltage drops and then subtract from voltage source. Going both directions does not give same result but it should. Answer should be 10.48 Volts meaning I should do 9+1.48 but why is one side subtract from voltage source and one is add voltage source?
I write this in a hurry. If not understand I can explain more clear. Please let me know.