Answer:
Only one solution
Explanation:
There's the theorem that states for a polynomial of nth degree will always have n amount of solutions.
A linear equation always have one solution.
A quadratic equation always have two solutions.
A cubic equation always have three solutions.
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A nth polynomial equation always have n solutions.
However, the theorem works when we set the variable that we want to solve to be able to hold set of complex number.
Therefore, from theorem, we can conclude that x+1 = 0 has only one solution since it only has one degree.