Elimination Quiz

Solve the System by Elimination

x - y = 11

2x + y = 19

• (10,-1)

• (-1,10)

• (3,-4)

• (6,7)

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 system using elimination

• cross out the 2x and 3x

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

• change to slope intercept form and graph

What do you get when you add the system below?

9x + y = 12

-9x + y = 6

• -18x = 18

• y = 18

• 2y= 18

• 18x + 2y = 18

Should you Add or Subtract to eliminate a variable in the equations below?

2x - 6y = 20

2x + 5y = -11

• Subtract

• Add

Solve by elimination 
-2x + 6y = 16
-4x  - 3y = 2

• (2,2)
• (-2, -2) 
• (-2,2)
• (2,1)

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

After solving algebraically, how can you check your answers?

• Plug x and y back into both your equations and see if they "check out"

• graph the lines in desmos and see where they intersect

• all of the above

Tags

CCSS.8.EE.C.8B

CCSS.HSA.REI.C.6

When doing elimination, select the steps that are used. (you can choose more than one)

• Make sure the equations are lined up.

• Go for a run.

• Add or Subtract to eliminate a variable.

• Solve for the remaining variable.

Solve the system by elimination.

8x +10y = - 20

−8x − 6y = −4

• Infinite number of solutions

• (6, 5)

• (−6, −5)

• (5, −6)

• No Solution

Tags

CCSS.8.EE.C.8B