Solving Systems of Equations by Elimination

​elimination Method

1. Line up like terms for all equations

2. Look for inverse coefficients that will eliminate one variable. If you can't find some, make some by multiplying

3. Eliminate one variable by adding the equations Vertically

4. solve for the other

5. Use the new value from #3 to find the other variable's value

When is best to solve by graphing? substitution? elimination?

Examples

1. 3x + x = 4

   y - 2x = 6

2. 3x - 2y =2

   -3x + 5y = 13

Multiple Choice

Solve the following system by elimination.

$$x+y=8\ and\ x=y=-2$$

• (2, 6)

• (5, 3)

• (6, 4)

• (3, 5)

Multiple Choice

Solve the following system by elimination.

$$2x-3y=14\ and\ x+3y=-11$$

• (1, 6)

• (8, 2)

• (1, -4)

• (-2, 6)