Lesson 7.2 Solving by Substitution.notebook
January 24, 2012
7.2 Solving Systems using Substitution
Objective:
Be able to solve systems of equations using substitution
Methods for Solving Systems of Equations
Graphing
Substitution
Elimination
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Lesson 7.2 Solving by Substitution.notebook
January 24, 2012
Example 1
Graph both equations on the axis provided and estimate the intersection
y
x
SUBSTITUTION
Solve this system using the substitution method.
Hint: They are both equal to y.
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Lesson 7.2 Solving by Substitution.notebook
January 24, 2012
Example 2:
Substitution!
Find the exact value for y using the substitution method
y= ­2x + 4
y= 3x ­ 6
Example 3
Graph these two equations on the same axis. Where do they intersect?
y
y = 3x ­ 2
y = 5x + 1
x
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Lesson 7.2 Solving by Substitution.notebook
January 24, 2012
Now solve using substitution
y = 3x ­ 2
y = 5x + 1
On the board before we can leave!!!
Solve using substitution
Page 384 #5, 7, 9, 10
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