Question 1043142
  -2c + b =

How can this be solved? Don't you need to be given the value of one of the variables or the answer to solve?
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1st, there's nothing on the right side. --> not an equation, nothing to solve.
-2c + b = ??? what?
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If there were a constant on the right side, it would be 1 eqn in 2 variables.
No unique solution.