How to Solve Polynomials on a TI-84 Plus

By Chance E. Gartneer; Updated April 24, 2017
Learning how to factor out monomials can help you solve polynomials.

A polynomial is an algebraic expression composed of terms. Each term is a variable raised to a given exponent combined with a coefficient. A polynomial is classified by its degree, which is the greatest exponent amount of one of its terms. The polynomial's degree can be an indication of how many roots, or values for the variable, it has. The TI-84 Plus graphing calculator has a specific function that solves polynomials and defines their roots.

Press the "Apps" button. The "Applications" menu will be displayed on the screen.

Press the downward arrow button of the joystick keypad to scroll down the screen to the "PlySmlt2" option. Press "Enter" to select. A title, "Poly Root Finder and Simultaneous Eqn Solver," will appear. Press any key to continue.

Press the downward arrow key to scroll to the "Poly Root Finder" option, and then press "Enter." The "Options" menu will appear.

Press the downward arrow button to scroll to the "Order" option, and then press "Enter." Press the left-pointing and right-pointing arrow buttons to select the degree of the polynomial. For this example, the polynomial is x³ - 6x² + 11x - 6 = 0, so press the right-pointing arrow to scroll to "3," and then press "Enter."

Press the "Graph" key, which is located on the right underneath the screen. A screen will appear with a general polynomial with the same selected degree. The corresponding coefficients will be listed under the polynomial. Enter the value of the coefficient of the greatest term, and press "Enter." For this example, the coefficient of the leading term is 3, so enter "1" and then press "Enter." Repeat this process with the remaining coefficients. For this example, enter "-6," "11," and "-6," pressing "Enter" after entering each term.

Press the "Graph" key to solve the polynomial. A screen will appear with the same general polynomial along the top, and the roots of the polynomial listed under the polynomial. For this example, the values of x will be 1, 2 and 3.

About the Author

Chance E. Gartneer began writing professionally in 2008 working in conjunction with FEMA. He has the unofficial record for the most undergraduate hours at the University of Texas at Austin. When not working on his children's book masterpiece, he writes educational pieces focusing on early mathematics and ESL topics.