Geometry Glossary - E
 

Edge of a polyhedron:

the intersection of two faces of a polyhedron

Edge:

part of a solid formed by two faces, or a face and a base intersecting

Equation of a circle:

r = (x-h) + (y-k).

Equation of a line:

slope-intercept form: y=mx+b

general form: Ax + By = C

point-slope form: y - y¹ = m(x - x¹ )

Equiangular triangle:

a triangle with three congruent angles

 

Equilateral triangle:

a triangle whose sides are all congruent

Euclidean transformation:

any one of three types of manipulations, or functions, (translations, rotations, reflections) that can be performed on a geometric figure to generate a figure that is differently oriented or located on a graph; may alternately be called slides, turns, and flips; coupled with a change in magnitude (scale change), transformations may also result in a shrink or stretch of the original figure

Exterior angle of a triangle:

an angle that forms a linear pair with any angle of the triangle (or polygon)