Jon M. Plachy

Jon M. Plachy of Centennial, Colorado, died on November 9, 2025. He was 92 years old.
Jon was born in Barranquilla, Colombia, South America, on January 22, 1933. He graduated from Greeley, Colorado, Central High School. He later earned a bachelor's degree in mathematics from Adams State University and a master's degree in mathematics from Louisiana State University. In 1964, he received a Ph.D. from Oklahoma State University.
Jon served his country as a Specialist 4 in the United States Army. He attended the Army Language School at the Presidio of Monterey, California. During the Cold War, Jon served for three years as a German Translator for the Army Security Agency in Frankfurt, Germany.
Jon married Sondra Jo Self in August 1962. In 1965, Jon and Sondra moved to Denver, Colorado, where Jon joined the faculty of Metropolitan State College as a Professor of Mathematics. He served the College as Chairman of the Division of Science and Mathematics. At the time, Metro was a new college with just 1,156 students. Now known as Metropolitan State University, the school now has an enrollment in excess of 16,000.
One of Jon's accomplishments at Metro was the establishment of an intercollegiate athletic program for men and women. Jon served as the head basketball and tennis coach for several years.
Jon retired from Metro in 2002 after a 37-year tenure. Upon retirement, he was granted the title Professor Emeritus of Mathematics and Computer Science.
Jon was preceded in death by the love of his life, his wife Sondra, his lovely daughter Michele, his parents Fred and Margaret, and his siblings, Shirley and Frederic.
Jon is survived by his son Michael (Karen), his beloved grandchildren Meghan (Brent), Maxwell (Jenny), Madeline (Anthony), and Mallory (Dylan), and his great-granddaughter Blair Michele Traver.
A memorial service will be held at 1:30 p.m. on Wednesday, November 26 at Wellshire Presbyterian Church, 2999 S. Colorado Boulevard, Denver, Colorado. Jon was a member of Wellshire for over sixty years. A family burial service was held earlier at Fairmount Cemetery in Denver. In lieu of flowers, memorial gifts may be made to the Michele Plachy-Rubin Memorial Fund at the University of Colorado or the Wellshire Presbyterian Church Special Music Fund.