Module 2: Lesson 3
 
Are You Ready?
  1. There are two methods that could be used to solve the equation.

    Method 1: Use a Single Function

    Rearrange the equation so that the equation equals zero.

     


    Graph the function y = 2x2 − 4x − 6 and determine the x-intercepts of the graph. These are also considered the zeros of the function.

    You can use a graphing calculator to determine the x-intercepts of the graph. If you are unsure of this process, consult your calculator manual or your teacher.

     
    This is a graph of the quadratic function y equals 2 times x squared subtract 4x subtract 6. The x-intercepts of the graph are labelled at (negative 1, 0) and (3, 0).

    The x-intercepts are −1 and 3. The solutions to the equation are x = −1 and x = 3.

    Method 2: Use a System of Two Functions

    Write each side of the equation as a function.

     
    y = 2x2 − 4x and y = 6

    Graph each function and determine the x-coordinates of the points of intersection between the two functions.

    You can use a graphing calculator to determine the points of intersection. If you are unsure of this process, consult your calculator manual or your teacher.

     
    This is a graph of two functions. The quadratic function y equals 2 times x squared subtract 4x and the function y equals 6. The points of intersection of the two functions are labelled at (negative 1, 6) and (3, 6).

    The x-values of the intersection points are −1 and 3. The solutions to the equation are x = −1 and x = 3.


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