What is -12 = 12 ? I think it is one solution, but I'm not sure.
If you are talking about solving an equation, with the variable being eliminated and you are left with -12 = 12, then
that means there is no solution.
When solving an equation, if the variable disappears and you are left with a false statement, such as -12 = 12,
there is no solution.
If the variable disappears and you are left with a true statement, such as 4 = 4, then there are infinite solutions.
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