If the circuit current is 3 A, what is the value of R3?
72 volts
R1= 36Ω
R2= 50 Ω
R3=?

Answer:
22 Ω
Explanation:
0) to re=write the given schema;
1) to write common equation of U[V];
2) to calculate the value of the current I₁ [A];
3) to write the common equation of current I [A];
4) to calculate the value of the current I₂₃ [A];
5) to calculate the value of R₃ [Ω] using the common equation of U.