5.4  Modeling Quadratic Functions Grapher

Modeling Quadratic Functions - Grapher

Using the Graphing Calculator

     We worked through the process of finding the linear regression line and plotted the data points using a graphing calculator. 

   Now you will do the same using the given data in the above problem to find the quadratic regression line.

      {(0,4), (0,6), (5, 10), (5,7), (10, 12), (10, 10), (15, 15), (15,17), (20, 18), (20, 21), (25, 20), (25, 21), (30, 21), (30, 22), (35, 21), (35, 20), (40, 19), (40, 20)}

    ~  Use the information in Lesson 5.3C:

          I copied and pasted the first couple of steps with a few changes so you can graph a quadratic equation rather than a linear equation. 

                  Note the changes (highlighted in red).

   ~  Press the STAT button

   ~  Press 1: Edit

   ~  Type the x data under L1: 

   ~  Type the y data under L2:

   ~  Once you typed in the data, Press the STAT button.

   ~  Move your cursor to CALC.

   ~  Press 5: QuadReg.

   ~  A screen with the following will appear:  QuadReg , press ENTER.

    Complete the rest of the steps, then compare your answers to the ones you found using DESMOS.

      Are they the same? If not, what went wrong? If you have questions, just ask!