Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1

6.1 Solving Systems by Graphing

Warm-Up:Graph the following equations:

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Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1 2

Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1 3

Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1 4

System of Equations- Two or more linear equations form a system of

equations.- Any ordered pair that makes all of the equations in a

system true is a solution of a system of linear equations.

Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1 5

Ex 1 Solving a system of equations by graphing.

What is the solution of the system? Use a graph.y=x+2y=3x-2

Think: How does graphing each equation help you find the solution to the system of equations?

Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1 6

Ex 1 Solving a system of equations by graphing.

What is the solution of the system? Use a graph.y=x+2y=3x-2

Start by Graphing both lines:

y = x + 2

y = 3x - 2

Where do they intersect?Check your answer with BOTH equations.

Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1

Got It?What is the solution of the system? Use a graph and check your answers:

y = 2x + 4y = x + 2

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Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1

- A system of equations that has at least one solution is consistent.

- A consistent system of equations is independent if it has exactly one solution.

- A consistent system of equations is dependent if it has infinite amount of solutions.

- A system of equations that has no solution is inconsistent.

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Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1 9

Think: Without graphing any equations, how could you tell how many solutions there will be?

Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1

Ex 3: What is the solution of each system?A. 2y - x = 2

y=(½)x + 1

B. y = 2x + 2y = 2x - 1

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Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1

Satellite RadioOne satellite radio service charges $10 per month plus an activation fee of $20. A second service charges $11 per month plus an activation fee of $15. In what month was the cost of the service the same?

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Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1 12

Objective: To Solve Systems of Equations by Graphing Content Standard: A.REI.6 Section 6.1

Homework: p.367 #13-20, 25-30, 34-36, 41

Before you leave today, you must show me you have the correct answers (with work) for problems: 17, 20, and 26. This is half your homework grade.

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