5.2 Elimination and Substitution

Which method would be best (quickest) for solving the system below:
3x - 4y = -2
y = 2x + 1

• Substitution
• Elimination
• Graphing
• None

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Which variable would be the "easiest" to eliminate?

• x (I would just need to multiply by the bottom equation by 2)

• y (I would just need to multiply the top equation by -7 and the bottom equation by 12)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What would you multiply the top equation by to eliminate x?

• Multiply the top equation by −2

• Multiply the top equation by −10

• Multiply the top equation by 4

• Multiply the top equation by −4

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

When using substitution, once you get the lonely variable by itself and substitute, what does the equation look like?

• 2(−4x+16)+3y=20

• 2(4x+16)+3y=20

• 2x+3(−4x+16)=20

• 2x+3(4x+16)=20

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system:
x + y = 19
y = 3x - 1

• (14, 5)
• (11, 8)
• (5, 14)
• (8, 11)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system of equations:
y=5x+3
y=-2x-4

• (2,-1)
• (-1,-2)
• (1,-2)
• (-2,-1)

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

y = 3x - 1
2x + 2y = 22

• (2, 5)
• (3, 8)
• (4, 11)
• (5, 14)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

x - 5y = 5
3x + y = 31

• (10, -1)
• (9, 4)
• (10, 1)
• (55, 10)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system of equations:
4x+8y=20
-4x+2y=-30

• (-7,1)
• (2,-5)
• (-2,5)
• (7,-1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6