Elimination Method System of Equations

4x+8y=20

-4x+2y=-30

• (-7,1)

• (2,-5)

• (-2,5)

• (7,-1)

When using elimination we need to have _________________.

• Inverses/Opposites

• Negatives

• Positives

• graphs

When using elimination, you need to have the variables lined up.

• True

• False

Determine how many solutions the system has.

• One Solution

• No Solutions

• Infinitely Many Solutions

• Mikey is my friend.

Determine how many solutions the system has.
(Hint:  Both lines are graphed over each other)

• One Solution

• No solution

• Infinitely Many Solutions

• I am Spartacus!

 4x + 8y =  20
-4x + 2y = -30

• (-7,1)

• (2,-5)

• (-2,5)

• (7,-1)

Solve by elimination 
  2x + 9y = -7
6x - 3y = 9 

• (-1, -1) 

• (2,-1)

• (1,1)

• (1,-1)

a method to solving a system of equations by getting rid of one of the variables first to solve for the other variable. 

• Systems by Graphing

• Systems by Substitution

• Systems by Elimination

• Systems by Drawing

5x - y = 12

3x + y = 4

Will you add or subtract to "eliminate" the y variable?

• add

• subtract

What action can you take to create equivalent coefficients so that the "elimination" method can be used?

• Multiply the top equation by 4

• Multiply the top equation by 2

• Multiply the bottom equation by 2

• Multiply the bottom equation by 4