Consider the dual supply circuit using E1 = 10 volts, E2 = 15 volts, R1 = 4.7 k, R2 = 6.8 k and R3 = 10 k. To find the voltage from node A to ground, mesh analysis may be used. This circuit may be described via two mesh currents, loop one formed with E1, R1, R2 and E2, and loop two formed with E2, R2 and R3. Note that these mesh currents are the currents flowing through R1 and R3 respectively.