7­2 Solving Systems Substitution.notebook
7-2: Solving Systems of Equations
Using Substitution
Objective:
• You will be able to solve a system of equations using substitution.
Problem: What if you're graphing and you don't get a "nice, neat" point? Then what??
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Solution:
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7­2 Solving Systems Substitution.notebook
Definition:
substitute:
Steps for solving a system of equations using substitution:
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Examples:
Solve each system using substitution. Check your answers.
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7­2 Solving Systems Substitution.notebook
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7­2 Solving Systems Substitution.notebook
Remember:
When you graph systems of equations, there are 3 possible outcomes:
1. the lines can cross once,
2. the lines can be the same and cross everywhere, or
3. the lines can be parallel and never intersect
The same 3 things can happen when you solve systems of equations using substitution:
1. If the lines intersect once, you will get one value for x and one value for y.
2. If the lines intersect everywhere, you will get a true statement of equality.
3. If the lines intersect nowhere, you will get a false statement of equality.
Practice Problems:
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7­2 Solving Systems Substitution.notebook
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