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Solve by Graphing
Solve by Substitution
Solve by Elimination
Vocabulary
Which Method Is Best?
100
y=-x-1

y=2x-10

(3,-4)
100

y=3x+4

y=10

(2,10)
100
2x-2y=6

2x+2y=14

(5,2)
100
Two or more equations being solved at once
What is a system of equations?
100
2x+y=4

10x-y=8

Elimination
200
y=-x+3

y=2x

(1,2)
200
y=6x-4

y=-2x+28

(4,20)
200

x-2y=9

3x+2y=-13

(-1,-5)
200
The answer to a system of equations
What is a solution?
200
y=3x-4

y=-x+4

Substitution
300
y=1

y=x+2

(-1,1)
300
y=x-2

2x+2y=4

(2,0)
300
2x+4y=8

-20x-4y=28

(-2,3)
300
Two lines that will never intersect
What are parallel lines?
300
y=(1/2)x+3

y=2x-2

Graphing
400

y=2

x=3

(3,2)
400
2x-3y=-4

x=7-3y

(1,2)
400

x+y=8

x-y=4

(6,2)
400
Two lines whose slopes are opposite reciprocals
What are perpendicular lines?
400
4x+2y=16

x=2

Substitution
500
y=-2x+1

y=-2x-3

No Solution
500
y+4x=-3

2x+5y=-15

(0,-3)
500
3y=4x-2

y=2x-2

(2,2)
500
The form of an equation written as y=mx+b
What is slope-intercept form?
500
2x-4y=12

-8x+16y=-48

Elimination