Education Technology

What Goes Up Must Come Down

Published on 06/09/2008

Activity Overview

In this activity, students use the calculator to solve quadratic equations. They use the quadratic formula to determine the vertex and the x-intercepts of the graph of a quadratic function.

Before the Activity

  • See the attached PDF file for detailed instructions for this activity
  • Print pages 69 - 72 from the attached PDF file for your class
  • During the Activity

    Distribute the pages to the class.

    Follow the Activity procedures:

  • Perform symbolic manipulation of the quadratic equation, use the calculator to solve the expression, and indicate both positive and negative solution
  • Use the solution in the original equation and confirm the results
  • Solve real world problems involving quadratic equations


  • Use the function model for the height of a projectile and complete the time versus height data table
  • Graph the function and find the maximum height for the projectile, time taken to reach the height, and time the ball remained in the air


  • Solve the given quadratic formula for projectile motion and answer the questions
  • Examine the graph of a quadratic function and realize that the shape is a parabola
  • Determine the axis of symmetry (vertical intercept), and the x- or y- intercepts
  • Understand the meaning of the intercepts and the vertex
  • After the Activity

    Students solve the equations and problems on the Student Activity pages.

    Review student results:

  • As a class, discuss questions that appeared to be more challenging
  • Re-teach concepts as necessary