Solving Systems of Equations by Elimination with Addition and Subtraction

• -1

• 6

• 1

• -6

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

• (6, 10/3)

• (6,5)

• (4,5)

• (4,-5)

Tags

CCSS.HSA.REI.C.9

• 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

• Multiply the entire first equation by 2

• Multiply the entire first equation by -2

• Multiply the entire second equation by -1

• Multiple the entire first equation by 7

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

• (1,2)

• (-1,2)

• (1,-2)

• (-1,-2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6