Systems by Elimination Which Variable Will Be Eliminated

Systems by Elimination

5) y = ___

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Systems by Elimination

6) x = ___

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Systems by Elimination

5) x = ___

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Which variable would be easiest to eliminate?

• x

• y

• Neither

Answer explanation

The terms with x in them have opposite coefficients (4x and -4x), so they will be the easiest to eliminate when we add the equations together.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

To eliminate a variable in the system, should you add the equations or subtract the equations?

• Add

• Subtract

• Neither

Answer explanation

We want to add the equations together in order to eliminate one of the variables. We have opposite terms (3x and -3x) that will "cancel/zero out" (be eliminated) when we add the equations together.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the following using elimination.

• (10,-1)

• (-1,10)

• (-1,-10)

• (-10,-1)

Answer explanation

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve using Elimination:

5x + y = 9

10x − 7y = −18

• (4, -11)

• (1, 4)

• (-1, 14)

• (-4, 29)

Answer explanation

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination
-6x + 5y = 1
6x + 4y = -10

• (1,-1)

• (0,-1)

• (1,1)

• (-1,-1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination:
7x + y = -9
-3x - y = 5

• No solution

• (1,8)

• (-2,-3)

• (-1,-2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve by elimination:
x + 9y = 8
-6x - 9y = -3

• (1,-1)

• (1,1)

• (-1,1)

• (-1,-1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6