Lesson 12
Changing the Equation
These materials, when encountered before Algebra 1, Unit 6, Lesson 12 support success in that lesson.
Lesson Narrative
In this lesson, students prepare for the associated Algebra 1 lesson by focusing on evaluating quadratic expressions correctly, particularly for a negative input (for example, evaluating \(x^2+10\) when \(x\) is -3). Additionally, they recall the effect on a graph of a linear function when its parameters vary. Students will encounter and rehearse some language needed to describe the effect of varying the parameters \(a\) and \(c\) in a function defined by \(ax^2+c\) in the associated Algebra 1 lesson. When students evaluate sample work and explain who they agree with and why, they are critiquing the reasoning of others (MP3). When students vary the parameters in a linear function and record their observations, they have an opportunity to attend to precision through their word choices (MP6).
Learning Goals
Teacher Facing
- Evaluate quadratic expressions for negative values of the variable.
- Revisit the effect on its graph of changing the parameters in a linear function.
Student Facing
- Let's look at quadratics with negative inputs.