J.R. S. answered 11/11/21
Ph.D. University Professor with 10+ years Tutoring Experience
Please see my answer to your other redox balancing question for a step by step approach.
V2+ is the reducing agent and V(OH)4+ is the oxidizing agent
V2+ + H2O + 2OH- ==> VO2+ + 2H2O + 2e-
V(OH)4+ + 2H2O + 1e- ==> VO2+ + 3H2O + 2OH- [x2]
V2+ + H2O + 2OH- ==> VO2+ + 2H2O + 2e-
2V(OH)4+ + 4H2O + 2e- ==> 2VO2+ + 6H2O + 4OH-
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V2+ + 2V(OH)4+ ==> 3VO2++ 3H2O + 2OH-