Solve Using Elimination

Describe the error in solving the system of equations using elimination:

• They eliminated the x terms when they should have eliminated the y terms.

• The subtracted 5x and x to get 4x, but they should have added the x terms to get 6x = 24.

• They added 16 and 8 to get 24, but they should have subtracted them to get 8 on the right side of the equation.

• They eliminated the y terms, but they couldn't because one is a negative and one is a positive.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve using elimination. 
 4x + 8y = 20
-4x + 2y = -30

• (-7,1)

• (2,-5)

• (-2,5)

• (7,-1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system using elimination.
3x + 2y = 16
7x + y = 19

• (-2,5)

• (-2,-5)

• (2,-5)

• (2,5)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• ( 4 , -3 )

• ( -3 , 4 )

• ( 3 , 4 )

• ( 4 , 3 )

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination:
4x+9y=28
-4x-y=-28

• (-7,0)

• (6,0)

• (-6,0)

• (7,0)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination:

7x + y = -9

-3x - y = 5

• No solution

• (1,8)

• (-1,-3)

• (-1,-2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What would be the first step in finding the solution with elimination?

4x + 3y = 1

x - 3y = -11

• cross out the 3y and -3y

• cross out the 4x and x

• change all the signs of the second equation

• add 1 and -11

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system using Elimination.

-4x - 5y = 10

8x + 6y = 4

• (6, 5)

• Infinitely Many Solutions

• (-6, -5)

• (5, -6)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Use the Elimination method to solve the system.

-7x - 5y = 12

7x + 5y = -12

• (0, 0)

• (1, 1)

• Infinitely Many Solutions

• No Solution

Tags

CCSS.8.EE.C.8B

Solve the system using the Elimination method.

-7x + 6y = 29

10x + y = 16

• (1, 6)

• (-1, 3)

• (-3, -1)

• No solution

Tags

CCSS.8.EE.C.8B