Two problems related to the mean-value theorem lead into a problem requiring the use of the universal chord theorem. This latter theorem is discussed and a proof given. (MP)

Two mathematical brainteasers, with solutions depending on involved trial-and-error processes, are shown to have ingenious solutions. (MP)

An example is given of a problem-solving approach by outlining the development of a generalization of the Pythagorean Theorem as applied to points on a unit circle. (MP)

Nine examples of this principle show what a powerful tool it is. Several map coloring theorems are proven and some exercises are listed. (MP)

Theorems about the hyperbola which are ordinarily introduced in calculus courses can be proved without using the calculus. (SD)

A method of approximating areas under curves in precalculus courses is described. (SD)

Using a computer equipped with a plotter, graphs of linear equations and trigonometric identities can be produced. Examination of these graphs can aid in teaching solution of equations. (SD)

A technique for teaching the graphing of polar coordinate equations is presented. This approach involves the use of an auxiliary graph in rectangular coordinates and is thought to aid students in understanding of problem-solving situations such as in dealing with points of intersection and determination of limits of integration. (MP)

A college-level intermediate algebra course with an applications theme is described. (MK)

The game of "Sprouts" is explained, then several theorems concerning the game are stated and proved. (DT)