1. Lesson 2

1.4. Discover

Mathematics 20-1 Module 4

Module 4: Quadratic Equations and Inequalities

 

Discover
 

This shows a cartoon of two friends playing a number guessing game.

 

Try This 1
  1. Read the Apple Pi cartoon shown. On a scale of 1 to 10, rate how impressed you are that the girl guessed the correct integers?

  2. One of the numbers is easy to guess from the clue that is given. Which number is it and why should it be easy to guess that number?

  3. Consider the three quadratic equations in the chart. For each equation, determine the roots from the graph then factor the equation. You can use the chart to summarize your work.

     
    Quadratic Equation Graph Roots Factored Form
    a. x2 + 3x − 4 = 0 This shows the graph of the quadratic function y = x squared + 3x – 4.    
    b. x2 − 4 = 0 This shows the graph of the quadratic function y = x squared – 4.    
    c. 2x2 − 5x + 2 = 0 This shows the graph of the quadratic function y = 2x squared – 5x + 2.    

     

  4. How are the roots of a quadratic equation related to the factored form of the equation?

  5. Suppose the roots of a quadratic equation are 8 and –5. Given these roots, what are the possible factors and a possible quadratic that satisfies the roots?

course folder Save your responses in your course folder.

You will need to retrieve your work later in the lesson.

 

Share 1

 

With a partner or in a group, discuss your responses to Try This 1 questions 3 and 4. Summarize your discussion by answering the following question: How is the clue given in the cartoon related to finding the roots of a quadratic equation by factoring?

   

course folder If required, save your response in your course folder.