Electronic Proceedings of the Twentysecond Annual International Conference on Technology in Collegiate MathematicsChicago, Illinois, March 1114, 2010Paper C014
This is an electronic reprint, reproduced by permission of Pearson Education Inc. Originally appeared in the Proceedings of the Twentysecond Annual International Conference on Technology in Collegiate Mathematics, ISBN 9780321746146, Copyright (C) 2011 by Pearson Education, Inc. 
Solving Quadratic Congruences Modulo A Prime On The TI89 
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We consider the problem of solving the quadratic congruence: ax
^{2} + bx + c = 0 (mod p) where p is an odd prime number, using the TI89. The familiar quadratic formula may be used if we interpret the formula correctly. We will discuss the components needed to use the quadratic formula in this situation: modular exponentiation, modular inverses, finding square roots modulo a prime p, and implementing these on the TI89.
Keyword(s): number theory, TI89