Elimination Method

Linear Equations

100

Define Solution

Value for the variable that makes the equation true

200

Evaluate when x=3

8(x - 2) + 4x

20

300

Solve for x

7x + 8=22

x=2

400

Solve for y when x=2

y=40x + 25

y=105

500

Solve for x when y=4

3x - 3y=15

x=9

Solving Systems (1st Step)

100

Add the following equations

4x - 7y=42

9x + 7y=-16

13x=26

(Bonus Knowledge: x=2)

200

Subtract the following equations

14x + 3y=28

14x + 11y=-12

-8y=40

(Bonus Knowledge: y=-5)

Bonus Question (300): What is the goal when adding/subtracting equations?

300

Combine the equations to eliminate a variable

9x + 5y=46

4x +5y=31

5x=15

(Bonus Knowledge: x=3)

400

Combine the equations to eliminate a variable

8x + 7y=-22

-8x + 3y=22

10y=0

(Bonus Knowledge: y=0)

Bonus Question (400): How do we know when to add or subtract the equations?

500

Combine the equations to eliminate a variable

x + y=18

x - y=14

2x=32

2y=4

(Bonus Knowledge: x=16, y=2)

Solving Systems (Step 2)

100

Solve for y

 2x + 5y=20

-2x + 3y=-4

         8y=16

y=2

200

Solve for y, use the system below and x=5

9x + 5y=–5

6x + 5y=–20

y=-10

300

Solve for x, use the system below and y=-9

x + y= 1

10x + 9y=19

x=10

400

Solve for y, use the system below and x=-1

3x − 2y=1

3x + 7y=–17

y=-2

500

Solve for x, use the system below and y=-1

6x − 6y=–12

6x − y=–17

x=-3

Elimination Method

100

What is the value of x for this system of equation?

–2x + y=12

–2x − y=4

-4

200

Find the solution to...

4x + 5y=–20

-9x - 5y= -5

 ( 5, 8)

300

Which of the following is the solution to...

9x + 5y=2

9x + 7y= -8

(3, -5)

400

What is the solution to...

5x − y=–4

10x − y=1

C. (1, 9)

500

DOUBLE POINTS!!!   Find the solution

–4x − 7y = 2

3x  - 3y = 6

(4, 2)