#### Cynthia Lanius Thanks to PBS for permission to use the Pyramid photo.

# Glossary

## geo (earth) - metry (to measure)

 circle the set of all points in a plane a given distance from a given point. congruent equal measure hexagon a six-sided polygon heptagon a seven-sided polygon octagon an eight-sided polygon parallelogram a quadrilateral with both pairs of opposite sides parallel pentagon a five-sided polygon similar figures that have the same shape, but not necessarily the same size rectangle a quadrilateral with 4 right angles trapezoid a quadrilateral with exactly one pair of opposite sides parallel - isosceles a trapezoid with the un-parallel opposite sides congruent triangle a 3-sided polygon - equilateral a triangle with all sides congruent - isosceles a triangle with at least two sides congruent - right a triangle with a right angle - scalene a triangle with no sides congruent

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##### Copyright 1997-2008 Cynthia Lanius

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