A definition is given for curves parallel to a closed curve. Equations for inner and out elliptic parallels are derived and explained. (RS)

Brief articles on topological regular solids giving a proof of Euler's Theorem and the Regularity Theorem; calculus theorems; including a limit theorem, the Law of the Man, and the Intermediate Value Theorem, applied to catching calves, drunk cowboys, and the border of Montana Respectively; and a discussion of the inequality tan A<A<sin A…

Seven articles present: 1) a solution to a force equilibrium problem, 2) a magic square, 3) a characteristic of right triangles, 4) a family tree of Pythagorean triples, 5) a misunderstanding which may be cleared through modern mathematics, 6) a technique for solving conversion problems, and 7) a special permatation problem. (RS)

Instructions are given for constructing a geometric figure called the arbelos'' or shoemaker's knife,'' then properties of this figure are investigated in nine theorems. (DT)

This material shows how to use basic techniques, principles of counting, and geometry to count squares on geoboards. The methods are elementary in that the proofs are easily conceptualized. A discussion of other approaches illustrates that easily stated problems may lead to very difficult and sophisticated methods. (MP)

A possible logical flaw based on similar triangles is discussed with the Sherlock Holmes mystery, "The Muskgrave Ritual." The possible flaw has to do with the need for two trees to have equal growth rates over a 250-year period in order for the solution presented to work. (MP)

A Norman window consists of a semi-circular section mounted surmounting a rectangular section. Modifications to a simple problem are presented that assume parts of the window are made with stained glass. The goal is to maximize the level of light transmission with a fixed perimeter. (MP)

The use of basis matrix methods to rotate axes is detailed. It is felt that persons who have need to rotate axes often will find that the matrix method saves considerable work. One drawback is that most students first learning to rotate axes will not yet have studied linear algebra. (MP)

Examples of some geometric illustrations of limits are presented. It is believed the limit concept is among the most important topics in mathematics, yet many students do not have good intuitive feelings for the concept, since it is often taught very abstractly. Geometric examples are suggested as meaningful tools. (MP)

This volume, a reprinting of a classic first published in 1952, presents detailed discussions of 26 curves or families of curves, and 17 analytic systems of curves. For each curve the author provides a historical note, a sketch or sketches, a description of the curve, a discussion of pertinent facts, and a bibliography. Depending upon the curve,…

Geometric enrichment activities used with prospective elementary school teachers were found to not significantly affect attitude toward mathematics or achievement in a geometry course; the only factor which significantly affected student achievement in this study was the instructor. (DT)

People are noted as intrigued for centuries by interplay between algebra and geometry with many important advances viewed to have come down through some sort of linking of the two. Examples are given of advantages to learning and discovery that can be found in an investigative approach combining them. (Author/MP)