Geometry Glossary Chapter 1

Front 1

Postulate 1

Back 1

in a ray, there exists exactly 1 point a given distance from the end point.

Front 2

Postulate 2

Back 2

'B' is in between 'A' and 'C' if and only if AB + AC = AC.

Front 3

Postulate 3

Back 3

in a plane with a given ray, there exists exactly 1 ray in a half-plane (formed by a line) a given measure from the given ray.

Front 4

Postulate 4

Back 4

if 'D' is on the interior of ABC, then ABD + DBC = ABC.

Front 5

Postulate 5

Back 5

a line has at least 2 points; a plane has at least 3 points, space has at least 4 non-coplanar points.

Front 6

Postulate 6

Back 6

through any 2 points there exists exactly 1 line.

Front 7

Postulate 7

Back 7

through any 3 points there exists at least one plane; through any 3 non-collinear points there exists exactly one plane.

Front 8

Postulate 8

Back 8

if a plane contains 2 points, the line that contains those points is in the plane.

Front 9

Postulate 9

Back 9

if 2 planes intersect, they meet at a line.

Front 10

Theorem 1

Back 10

if two lines intersect, they meet at a point.

Front 11

Theorem 2

Back 11

through a line and a point not on the line there exists exactly 1 plane.

Front 12

Theorem 3

Back 12

if 2 lines intersect, then exactly one plane contains the lines.