Answer: A solution that results in a false statement when substituted back into the original equation.
Step-by-step explanation: An extraneous solution is one that arises in a solution of equations, but which on closer inspection is not a solution to the original equation. Therefore, they imply an error in the development of the solution of the equation, so they cannot be taken as a valid solution since, when replacing the result with the missing variable, the equation does not obtain the desired result.