The mathematical purpose of this lesson is to work with equivalent equations that are multiples of one another. In the first activity after the warm-up, students examine the effect on the graphs of the equation of multiplying an equation by a constant. In the second activity, students find a value that can multiply an equation to achieve a target coefficient for a given variable. In the associated Algebra lesson, students use the skill of multiplying an equation by a constant when solving systems of equations by elimination.
Students attend to precision (MP6) when they use precise language to describe a reason why a system of equations does not belong. Students look for and make use of structure (MP7) when they recognize two equations to be equivalent.
Lesson overview
- 16.1 Warm-up: Which One Doesn’t Belong: Systems of Equations (5 minutes)
- 16.2 Activity: Examining Equation Pairs (20 minutes)
- 16.3 Activity: Making the Coefficient (15 minutes)
Learning goals:
- Multiply an equation by a number to reach a target coefficient for a given variable.
- Recognize that multiplying an equation by a factor creates an equivalent equation with the same intercepts and slope.
Learning goals (student facing):
- Let’s learn how to check our thinking when using elimination to solve systems of equations.
Standards:
- This lesson builds towards the standards: CCSS.HSA-REI.C.5MS.A-REI.5CCSS.HSA-REI.C.6MS.A-REI.6MO.A1.REI.B.5MO.A1.REI.B.3
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