Solving Systems by Elimination

The solution is:

• (4, 3)

• (3, 4)

• (-4, 3)

• No solution

Tags

CCSS.8.EE.C.8B

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

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

What is the next step in solving this system by elimination?
2x + 3y = 9
5x + 3y = 21

• Nothing - it is ready to go.

• Multiply one equation by -1

• Multiply the top equation by 3.

• Multiply the bottom equation by 7.

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system.

• (2, -2, 3)

• (2, 1, 4)

• (-2, 2, -3)

• No Solution

Solve the system. 

• (5, -6, 3)

• (2, 3, -1)

• (-4, 2, 5)

• No Solution

Solve the system.

• (3, -2, 4)

• (2, -3, 1)

• (-3, 2, -1)

• Infinitely many solutions

Solve the system.

• (1, 2, -2)

• (1, -3, -2)

• (-1, 3, 2)

• No Solution

4x +  8y = 20
-4x + 2y = -30
Which variable will be eliminated?

• The  x

• The  y

• The  z

• The unknown

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