Solving Equations by Elimination Which Variable

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

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 do you have to multiply the first equation by to have the x's be opposite and the same?

• 3

• 2

• -2

• -3

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system of Equation (x,y)
x + 4y = –3
 x + 7y = –12 

• (-3,9)

• (9,-3)

• (3,9)

• (9,3)

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:
x + 6y = 17
x - 3y = 8

• (5, 2)

• (11, 1)

• (1, 11)

• no solution

Tags

CCSS.8.EE.C.8B

Which variable is the easiest to eliminate in this system?

• x

• y

• both

• neither

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Which variable is the easiest to eliminate in this system?

• x

• y

• both

• neither

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What would be the first step in solving this system using the Elimination Method?

• You cannot solve this using the Elimination Method.

• Cross out the 2x and 3x

• Add the like terms. The y terms will cancel out.

• Change to slope intercept form and graph

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6