Solving a System of Equations with Elimination

Select the best choice.

• 1

• 2

• 3

• 4

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

4x + 8y = 20
−4x + 2y = −30

• (-1, 7)

• (-7, 1)

• (7, -1)

• (1, -7)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

x − y = 11
2x + y = 19

• (-1, 10)

• (30, 19)

• (19, 30)

• (10, -1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

5x + y = 9
10x − 7y = −18

• (4, -11)

• (1, 4)

• (-1, 14)

• (-4, 29)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

8x + 14y = 4
-6x - 7y = -10

• (4, -2)

• (-2, 4)

• (0, 3)

• (4, -2)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the solution to the system?

• (0, 3)

• (1, -1)

• (-3, 1)

• (1, 3)

Tags

CCSS.8.EE.C.8B

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

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

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