Method of Elimination
Example:
Solve x + y = 6 and x  y = 2.
Solution:
In this method we eliminate one variable by addition or subtraction.
Given that x + y = 6 and x  y = 2.
In the above two equations, the coefficients of y are +1 and 1. They
have the same value and the signs are unlike.
If we add two equations the variable y will be eliminated.
 x + y = 6  1 
 x  y = 2  2 
Adding equations 1 and 2 we get 
2x = 8  
x = 8 / 2 = 4
Therefore, x = 4.
Substituting the value of x in the equation 1 or 2.
x + y = 6
4 + y = 6
y = 6  4
y = 2
Therefore, the solution set {(4,2)}.
Verification:
We have to verify the solution (4,2) if it satisfies both equations.
Substitute x = 4 and y = 2 in the equations.
x + y = 6 and x  y = 2
4 + 2 = 6 and 4  2 = 2
Therefore, the solution (4,2) is correct.
Directions: Choose the correct answer. Also write at least ten examples of your own.
