The authors hope to show how a geometric insight can add to the richness of our students' experiences when they first encounter the solutions to two equations in two unknowns.

This article describes how to determine your return on investment when deposits of varying amounts are made over irregular time intervals.

Characterizes those numbers that are the sum of consecutive natural numbers and counts how many such representations a given number has. (Author/NB)

Shows how the phenomenon of instability in the solution of a system of linear equations can be analyzed both algebraically and geometrically. (KHR)

Presents an activity that utilizes a digital camera to capture a stream of water from a faucet to study quadratic behavior using graphing calculators. (ASK)

Presents an extension of a Japanese mathematics lesson involving the area of a triangle and introduces concepts from trigonometry. (ASK)

Presents the general postage-stamp problem on Diophantine equations. Discusses ways to uncover all solutions to the problem. (ASK)

Some uncomplicated illustrations of how probability yields results that seem in conflict with traditional intuition are given. (MNS)

How min-max problems can be solved with trigonometry and without calculus is described. (MNS)

A square-dance number is defined as an even number which has the property that the set which consisted of the numbers one through the even number can be partitioned into pairs so that the sum of each pair is a square. Theorems for identifying square-dance numbers are discussed. (YP)