Solving Systems of Equations by Elimination

Solve the system by elimination.

−6x + 6y = 0

9x − 8y = 4

• (4, −9)

• Infinite number of solutions

• (−9, 4)

• (4, 4)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Nancy went to the grocery story.  On Monday she purchased 4 apples and 6 bananas for a total of $13.  On Wednesday she purchased 3 apples and 7 bananas for a total of $13.50.  Which system of equations represents the situation?

• 4x + 6y = 3
  13.5x - 13y = 6

• x + y = 4
  x - y = 6

• 4x + 6y = 13
  3x + 7y = 13.5

• 4x - 6y = 13
  3x - 7y = 13.5

Tags

CCSS.8.EE.C.8C

Homer sells tickets for admission to your school play and collects a total of $104. Admission prices are $6 for adults and $4 for children. He sold 21 tickets total. Solve the system:
x + y = 21
6x + 4y = 104

• (10, 11)

• (12, 9)

• (11, 10)

• (9, 12)

Tags

CCSS.8.EE.C.8C

What is the first step in solving a system of equations by elimination?

• Get both equations in standard form and line up the like terms.

• Get both equations in slope-intercept form.

• Get both equations equal to zero.

• Put the x terms first.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination:
7x-9y=29

7x+2y=-15

• (-4,-1)

• (-1.-4)

• (-1,4)

• (-1,6)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination:
9x-4y=7

x-4y=-17

• (-1,5)

• (-7,5)

• (7,5)

• (3,5)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

________________

are two or more equations that have the same variables and work together.

• graphing lines

• elimination method

• system of equations

• table

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination:
4x+4y=4

3x+4y=10

• (7,-6)

• (-6,7)

• (6,7)

• (7,6)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

what does the top equation need to be multiplied by to create a zero pair?

2x - 6y = 20

2x + 5y = -11

• -1

• 1

• -2

• 2

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

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

• (-1, -1) 

• (2,-1)

• (1,1)

• (1,-1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6