Systems of Equations Elimination Add

4x+ 9y = 28

-4x -y = -28

• (-7,0)

• (6,0)

• (-6,0)

• (7,0)

• (6,7)

Solve the system by elimination.  

12x + 36y = −3 
−12x − 36y = 0 

• (10, 1) 

• (−10, −1) 

•  (10, −1) 

•  No solution 

What is the solution?

• (1, -2)

• (-2, 1)

• (-4, 1)

• (2, 1)

2x + 9y = -7

6x - 3y = 9

Mathematical Equivalence

ON

Solve using elimination.

-6x-6y=18

6x+6y=-24

• (7,8)

• (-7,-8)

• no solution

• infinitely many solutions

Solve using elimination. 
−4x − 4y = 0
4x + 4y = 0 

• (−6, −4) 

• Infinite number of solutions  

• (−6, 10) 

• (6, 4) 

2x + 9y = -7

6x - 3y = 9

Mathematical Equivalence

ON

2x + 9y = -7

6x - 3y = 9

Mathematical Equivalence

ON

Solve by elimination: 7x - 9y = 29 7x + 2y = - 15

• (-4,-1)

• (-1.-4)

• (-1,4)

• (-1,6)

Solve by elimination.

6x - y = 2

-3x - 6y = 12

• (2,0)

• no solution

• (0,-2)

• infinite solutions