Quadratic Functions and Solutions

Lesson 8

Math

Unit 7

9th Grade

Lesson 8 of 13

Objective


Factor special cases of quadratic equations—difference of two squares.

Common Core Standards


Core Standards

  • A.SSE.A.1.A — Interpret parts of an expression, such as terms, factors, and coefficients.
  • A.SSE.A.2 — Use the structure of an expression to identify ways to rewrite it. For example, see x4 — y4 as (x²)² — (y²)², thus recognizing it as a difference of squares that can be factored as (x² — y²)(x² + y²).
  • A.SSE.B.3.A — Factor a quadratic expression to reveal the zeros of the function it defines.

Criteria for Success


  1. Identify features of two linear binomials that when multiplied together result in a quadratic binomial difference of two squares. 
  2. Factor and solve quadratic equations that represent a difference of two squares.
  3. Describe graphical features of quadratic functions that are differences of two squares.

Tips for Teachers


Lessons 8 and 9 look at specific cases of factoring quadratic expressions—difference of two squares and perfect square trinomials. Depending on the needs of your students, these lessons can be kept separate or combined together. These lessons are also a good opportunity to spiral in other factoring problems from Lessons 4–7. 

Fishtank Plus

Unlock features to optimize your prep time, plan engaging lessons, and monitor student progress.

Anchor Problems

25-30 minutes


Problem 1

Aaron says that when you multiply two linear binomials, you will always get a trinomial. Alison disagrees and finds an example where two linear binomials multiplied together produce a quadratic binomial. 

Find an example that demonstrates Alison’s claim is true.

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

Problem 2

Find the solutions to the quadratic equations below. 

a.  $${y=x^2-196}$$

b.  $${y=16x^2-121}$$

c.  $${y=75x^2-27 }$$

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

Problem 3

Graphs of two quadratic functions are shown below. 

Which graph represents a quadratic function whose equation is a difference of two squares? Explain how you know.

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

Problem Set

15-20 minutes


Give your students more opportunities to practice the skills in this lesson with a downloadable problem set aligned to the daily objective.

Target Task

5-10 minutes


Factor each expression completely.

a.  $${x^2-36}$$

b.  $${12x^2-3}$$

c.  $${6x^2+34x-12}$$

Additional Practice


The following resources include problems and activities aligned to the objective of the lesson that can be used for additional practice or to create your own problem set.

  • Include spiraled problems that cover various factoring examples seen so far

Next

Factor special cases of quadratic equations—perfect square trinomials.

Lesson 9
icon/arrow/right/large

Lesson Map

A7CB09C2-D12F-4F55-80DB-37298FF0A765

Topic A: Features of Quadratic Functions

Topic B: Factoring and Solutions of Quadratic Equations

Topic C: Interpreting Solutions of Quadratic Functions in Context

Request a Demo

See all of the features of Fishtank in action and begin the conversation about adoption.

Learn more about Fishtank Learning School Adoption.

Contact Information

School Information

What courses are you interested in?

ELA

Math

Are you interested in onboarding professional learning for your teachers and instructional leaders?

Yes

No

Any other information you would like to provide about your school?

We Handle Materials So You Can Focus on Students

We Handle Materials So You Can Focus on Students

We've got you covered with rigorous, relevant, and adaptable math lesson plans for free