Solving Systems of Equations Algebraically

What is a system of equations?

• 2 equations that have the same unknowns
• 2 equations that are lost on a graph
• IDK
• They aren't a real thing...Mrs. Brown made them up.

Which of the following is NOT a method to solve systems?

• Elimination
• Distribution
• Substitution
• Graphing

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Which of the following are ways to solve systems of equations? 

• Graphing
• Substitution
• Elimination
• All of the above

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

If a system of equations has no solution, what does the graph look like? 

• intersecting lines
• parallel lines
• skew lines
• intersecting lines

Tags

CCSS.8.EE.C.8A

Which variable will eliminate?

4x - 5y = -21

2x + 5y = 27

• x

• y

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Solve the system of equations.

• (-6, 30)

• (-2, 10)

• (44, 39)

• No solution

• Infinite solutions

Tags

CCSS.8.EE.C.8B

Solve:
y=8x+1
y=6x+3

• (1, 9)
• (4, 14)
• (0, 1)
• (2, 4)

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

Which answer has a correct first step for this system:

3x + 3y = 3

y = 3x + 5

• The variable is already isolated, so we've already solved the system.

• The variable is already isolated for y, so we substitute it in the first equation and solve for x

  3x + 3(3x + 5) = 3

• Free sha vaca doo

• The variable is already isolated for y, so we substitute it in the second equation and solve for x

  y = 3(3x + 3y) = 3

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

Which variable is the easiest to eliminate?
4x + 9y = 28
-4x - y = -28

• y
• x

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6