The material examines areas generated by combinations of: (1) Circles and Triangles; (2) Closely Packed Circles; and (3) Overlapping Circles. The presentation looks at examples of certain areas and at logical ways to generate the necessary algebra to clarify the problems and solve general cases. Ideas for extension are provided. (MP)

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)

The lesson described combines mathematics, science, and literature, and is easily adaptable for use with classes in basic mathematics, geometry, analytic geometry, or calculus. (MP)

The author explores relationships among the lengths of sides of a triangle, one of whose angles measures 60 degrees. A computer program designed to search for special triangles is included. (SD)

Three worksheets are provided to help secondary students explore relationships among the areas of a variety of similar figures constructed on the sides of right triangles. The activity is extended to include the relationship among the lengths of the sides of the right triangle. Included are several student worksheets. (DC)

The purpose of this lesson on classifying triangles is to aid students' discovery of the different characteristics of equilateral, isosceles, and scalene triangles through computer explorations using Geometric Supposer or GeoExplorer software. (MKR)

Discusses six examples that discover supplementary geometry theorems by using three elementary theorems about the relationships between angles and intercepted arcs in circles. Topics in the examples include angles formed by parallel lines and the sum of the interior angles of triangles, convex quadrilaterals, star polygons, and hexagons. (MDH)

Reported are the activities and findings of a geometry study administered in a sixth grade class using a LOGO-based computer environment primarily involving properties of isosceles triangles. A majority of the students progressed from an unfamiliarity with geometric notions to a successful working relationship even with complex geometric…

Presents 14 distinct methods to determine the sine of the angle formed by the line segments joining one vertex of a square to the midpoints of the nonadjacent sides. Nine methods were developed by mathematics club participants preparing for mathematics competitions and the remaining five by faculty members. (MDH)

Presents an activity centering on Baravelle spirals in regular polygons to review and connect a number of algebraic and geometric topics, as well as to involve students in formal calculations, visualization, pattern discovery, series, estimation, and recursion. (MKR)

The Chinese tangram puzzle was known as far back as 1813. It has remained popular ever since. It consists of seven simple polygonal pieces of card which can be assembled in the form of a square. The reader is presented with some popular shape such as the man or cat above, and then asked to construct this using the tangram pieces. There are whole…

This textbook covers geometry and trigonometry and presents problems for student consideration. Geometry principles are applied to surface and solid measurement. Tables of logarithms and logarithmic sines are included. [This book was translated from the French of A. M. Legendre. It was revised and abridged by Charles Davies.]

This textbook presents readings in geometry and the theory of infinitesimals.