The elimination methods mainly include substitution elimination, addition and subtraction elimination, whole elimination, substitution elimination, structure elimination, factorization elimination, constant elimination, and using proportional nature elimination.
Elimination method classification:
1, substitution elimination method
The substitution elimination method, referred to as substitution method for short, refers to expressing the unknown number of one equation in the equations with an algebraic expression containing another unknown number, substituting it into another equation, eliminating an unknown number and getting a solution.
2. Addition, subtraction and elimination method
The method of addition, subtraction and elimination refers to the use of the properties of equations to make the absolute value of the coefficients in front of an unknown number in two equations in the equation set equal, and then add or subtract the two equations to eliminate them, so that the equations only contain one unknown number, and then they can be solved.