Solve Systems of Equations with Elimination

What if you are solving a system and your variables cancel out and you end up with a statement such as: 1=12? What conclusion can you make about the system?

• the solution is 1

• there is no solution

• the solution is 12

• infinite solutions

What is the solution to the system?

• (-4,3,5)

• (2,-3,5)

• no solution

• infinitely many solutions

What if you are solving a system and the variables cancel out and you end up with a statement such as 3=3, what can you conclude about the system?

• the solution is 3

• there are no solutions

• you can't conclude anything

• there are infinite solutions

What would you solve for First?

• Solve for x

• Solve for y

• Solve for z

• (5,3,4)

Does the ordered triplet (2,1,-4) satisfy the system of equations above?

• Yes

• No

• No Clue

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

Solve the system by elimination.

7x - y = -10

-7x + 5y = -6

• (-2, -4)

• (-2, -1)

• (-4, -1)

• (6, -8)

Alexandra finds that she can give 3 haircuts and 2 hair dyes in 315 minutes. Giving 2 haircuts and 4 hair dyes takes 450 minutes.  Which system of equations represents the situation?

• 3x + 2y = 315
  2x + 4y = 450

• 3x + 2y = 450
  2x + 4y = 315

• 2x + 2y = 315
  3x + 4y = 450

When using any of the 3 methods to solve a system of linear equations the resulting solution is the same no matter which method is used.

• True; using any method will result in the correct solution.

• False; the solution varies because the solution depends on which method is used.

Solve by elimination:
-9x-4y=-20

5x+4y=4

• (-4,4)

• (4,4)

• (4,-4)

• (-4,-4)