Systems of Equations Using Elimination

• Add the x terms in the two equations and the y terms in the two equations so you get 3x + 8y = 11

• Multiply all terms in the top equation by 2 so that you  can eliminate the x terms

• Multiply the x in the first equation by -2 so you get -2x + y = 2

• Multiply all terms in the top equation by -2 so that you can eliminate the x terms. 

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

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

• (-2,2)

• (2,-2)

• (-2,-2)

• (-2, 1/2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• (16,19)

• (19,-16)

• (-19,-16)

• (19,16)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system by using elimination.

• (1, 4)

• (4, 1)

• (2, 4)

• (4, 2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• (-7, -1)

• (1, 7)

• (-1, -7)

• (7, 1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• (-3, 2)

• (3, 2)

• (-2, 3)

• (2, -3)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• (4, -2)

• (-2, 4)

• (2, 4)

• (2, -4)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system of equations using elimination.

• f = -2, g = 1

• f = -1, g = 2

• f = 1, g = -2

• f = 2, g = -1

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the following system of equations using the elimination method.

• infinite solutions

• (0, -2)

• no solutions

• (0, 2)

Tags

CCSS.8.EE.C.8B