Elimination Quiz

Solve the System by Elimination

x - y = 11

2x + y = 19

• (10,-1)

• (-1,10)

• (3,-4)

• (6,7)

^{What is the solution?} 

• 1
• -2
• (1, 2)
• (1, -1)

Tags

CCSS.8.EE.C.8A

What is the solution?
(Hint:  Both lines are graphed over each other)

• One Solution
• No solution
• Infinitely Many Solutions

Tags

CCSS.8.EE.C.8A

This system has _____ solutions

• no
• 1
• 2
• Infinitely many

Tags

CCSS.8.EE.C.8A

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 zero out.

• change to slope intercept form and graph

What is the resulting combined equation for the system below?

9x + y = 12

-9x + y = 6

• -18x = 18

• y = 18

• 2y= 18

• 18x + 2y = 18

What does the top equation need to be multiplied by to create a zero pair?

2x - 6y = 20

2x + 5y = -11

• 1

• -1

• -2

• 2

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

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

• multiplying the top or bottom equation by a scalar

• isolating one variable in terms of another, then substituting that into the opposite equation

• solving for one variable then plugging it back in to solve for the other

• adding the two equations together