0=(-9)
Explanation:
4x + 7 = -2 + 4x
4x + 7 = 4x -2
subtract 7 from both sides of the equation.
simplify your answer.
subtract 4x from both sides of the equation.
simplify your answer again.
4x + 7 = 4x -2
___-7 = 4x -7
4x __ = 4x -9
__4x = 4x -9
-4x = -4x -9
__0 = -9
the input is a contradiction: it has no solutions.