1. Let's solve systems of equations.
4-13: Learning Goals
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Let's solve systems of equations.

2. 4-13-1: True or False: Two Lines
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Launch - slide is animated - 5 minutes

3. 4-13-2: Matching Graphs to Systems
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Launch - slide is animated - 15 minutes - image is hyperlinked to student Desmos applet

4. 4-13-3: Different Types of Systems
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Launch - 15 minutes - slide is animated - image is hyperlinked to student Desmos applet

5. 4-13: Lesson Synthesis
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How can you know the number of solutions for a system of equations from its graph?
How can you know the number of solutions for a system of equations from their equations?
To highlight the connection between the number of solutions to a system of equations and features of its graph and equations, ask:
“How can you know the number of solutions for a system of equations from its graph?” (If the two lines intersect at a point, there is one solution. If the two lines are parallel and do not intersect, there are no solutions. If the two lines are drawn through the same points, there are infinitely many solutions.)
“How can you know the number of solutions for a system of equations from their equations?” (If the two equations have different slopes, there is one solution. If the two equations have the same slope and different y-intercepts, there are no solutions. If the two equations have the same slope and the same y-intercept, there are infinitely many solutions.)
If students do not make the connection themselves, remind them of their earlier conclusions about the number of solutions and equation in one variable has.

6. I can solve systems of equations using algebra.
4-13: Learning Targets
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I can solve systems of equations using algebra.
I can graph a system of equations.

7. 4-13-4: Two Lines Cool-down - 5 minutes
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Cool-down - 5 minutes