Sherri Messersmith has been teaching at College of DuPage in Glen Ellyn, Illinois, since 1994. She has over 25 years of experience teaching many different courses from developmental mathematics through calculus. She earned a bachelor of science degree in the teaching of mathematics at the University of Illinois at Urbana-Champaign and went on to teach at the high level for two years. Sherri returned to UIUC and earned a master of science in applied mathematics and stayed on at the university to teach and coordinate large sections of undergraduate math courses. Sherri has authored several textbook, and she has also appeared in videos accompanying several McGraw-Hill texts.Sherri lives outside of Chicago with her husband, Phil, and their daughters, Alex and Cailen. In her precious free time, she likes to read, play the guitar, and travel — the manuscripts for this and her previous books have accompanied her from Spain to Greece and many points in between.