Solving Polynomials Using Graphing Calculators

This is site provides basic information on how to solve a polynomial using a TI graphing calculator. For more information on using your TI calculator, please visit the Texas Instrument's homepage.

All examples are for the equation:

Solving Polynomials with the TI-83+

Using the Equation Solver:
Rearrange the equation to be solved so that it is in the form:

0 =

  1. Press [MATH].
  2. Arrow down to 0: Solver, Press [ENTER]
    This screen should appear:

You may have to arrow up to see the beginning of the screen. If there is an equation in the 0= part of the screen, delete the equation so that it will be ready to take the equation you want to solve.

  1. Using the Alpha keys and the variable key [x, t, o,n] enter the
    equation you want to solve . Example for the quadratic equation:

    Press [ALPHA] [A] [x,t,o,n] [^] [2] [+] [ALPHA] [B] [x,t,o,n] [+] [ALPHA] [C]

You have entered AX2 + BX + C into the eqn: 0= ________

  1. Press [ENTER].

Enter a value for A.
Arrow down to B and enter a value for B.
Arrow down to C and enter a value for C.

  1. Arrow back to X and Press [ALPHA] [solve]
    One of the roots for X will appear on the screen beside X= ___.

BE SURE to arrow over to the end of the solution to variable for which you have solved. When a number continues beyond the screen, be sure to arrow over to check the end of the number to see whether it ends with an exponent. You do not know the size of the number until you check for the exponent at the end.

Solving Polynomials with the TI-86+

The Polynomial Root Finder: The root finder solves up to 30th order real or complex polynomials.

  1. Press [2nd] [POLY] This Displays the POLY order screen.
  2. Enter the integer between 2 and 30 that describes the highest order or power in your equation. If second order, press [2] [ENTER]
  3. Enter the value for the coefficient for each term followed by the down arrow. For this example:
    A2 = 3
    A1 = 2
    A3 = -3
  4. Press [F5] to SOLVE The two roots will appears as the two possible values of x. In chemistry only one of these values will be meaningful given the problem you are
    solving.

This website was created and designed by Gretchen E. Potts.
For questions on site content, please email Gretchen-Potts@utc.edu.

Copyright © 2001 Gretchen E. Potts. All rights reserved.

DISCLAIMER: The author used her best efforts to develop a high quality website and to verify that the information and demonstrations contained therein are of sound scientific judgment. However, the author makes no warranties to that effect and the author shall not be legally liable or responsible for any damage that may result from errors or omissions in the website.