Solving System of Equations by Elimination

​Solving Simultaneous Equations by

Multiple Choice

4x +  8y = 20

-4x + 2y = -30

Which variable will be eliminated by adding the two equations?

• The  x
• The  y
• The  z
• The unknown

Multiple Choice

Now Our New System is :

$$21x\ +\ 15\ y\ =\ 27$$  

$$20x\ -\ 15y\ =\ 55$$  

If we use ELIMINATION method, then what variable are we getting rid of?

• 0

• x

• y

• both x and y

Multiple Choice

Solve:

3x - y = 11

x + y = 5

• x = 4

  y = 1

• x = 4

  y = -1

• x = -4

  y = 1

• x = -4

  y = -1

Multiple Choice

Solve the system of equations below (*): $$2x-3y=8$$   $$-2x+4y=-12$$  

• $$\left(-2,-4\right)$$  

• $$\left(-2,4\right)$$  

• $$\left(2,-4\right)$$  

• $$\left(2,4\right)$$  

Multiple Choice

Solve: $$3x-4y=26$$   $$2x-4y=20$$  

• x = 6

  y = -2

• x = -6

  y = -2

• x = -6

  y = 2

• x = 6

  y = 2