Solve Systems by Substitution and Elimination

Does the system have one, none or infinite solutions?

y = 2x -11

y = 2x +5

• One

• None

• Infinitely many solutions

Tags

CCSS.8.EE.C.8B

Solve the system by substitution:

x - y = 6

y - 2x = - 5

• (1,3)

• (-1,3)

• (-1,-7)

• (1,-7)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What would be the first step in finding the solution using elimination?

2x + 2y = -2

3x - 2y = 12

• you cannot solve this using eliminiation

• cross out the 2x and 3x

• cross out the 2y and -2y

• change to slope intercept form and graph

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

What is the solution to this system?
x= 7 - 2y
2x + y = 5

• (-1,4)
• (4,-1)
• (1,3)
• (3,1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

The first step in solving using the substitution method is __________.

• get x by itself
• get y by itself
• get either variable by itself
• add the equations together

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

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

Solve using elimination. 
−4x − 4y = 0
4x + 4y = 0 

• (−6, −4) 
• Infinite number of solutions  
• (−6, 10) 
• (6, 4) 

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve using elimination.
-4x - 6y = 6
4x + 6y = -4

• no solution
• (2,0)
• (-4,0)
• (0,0)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

The solution to a system of equations is any ordered pair that makes both equations true. 

• TRUE
• FALSE

Tags

CCSS.HSA.REI.C.9

Solve using substitution:

y = -6x + 5

-2x + y = 5

• (-3, -6)

• (-6, 3)

• (0, 5)

• (-3, 5)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6