Elimination

Elimination is a method of solving systems of equations by adding or subtracting multiples of equations together in order to 'eliminate' one of the variables. Once this has been done, the system can be solved as in the other methods.
 * Elimination**

Level 1: same coefficient opposite sign Level 2: same coefficient, same sign (subtraction) Level 3: coefficient 1, another coefficient (one multiplication) Level 4: two coefficients (LCM, two multiplications)