It's an equation with no solution.
A solution is the number that 'x' must be in order to make the equation a true statement.
Subtract 3x from each side, and you have -1 = +7
There's NO value for 'x' that can make that statement true. So the equation has no solution.
The equation 3 x − 1 = 3 x + 7 has no solution, as it simplifies to a contradiction. This means there is no value of x that makes the equation true. Thus, the equation is inconsistent.
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