geomtry term Flashcards
Point
A specific location is space. Is is an undefined term…does not have an actual sizze.
Line
Determined by at least 2 points. Extends indefinitely on both sides.
Plane
a flat surface that extends indefinitely in all directions. Undefined term, no thickness.
Space
A boundless, three dimensional set of all points.
Line segment
A part of a line that consists of 2 points which the line has a definite length.
Collinear points
Points that lie on the same line.
Betweenness of Points
Point Y is between points X and Z if and only if X, Y, and Z are collinear and XY+YZ=XZ
Coplanar points
Points that lie on the same plane
Ray
An initial point and from that point a line extends indefinitely on one side only.
Intersect
Two or more geometric figures intersect if they have one or more points in common.
Congruent segments
Segments that have the same measure
Addition Postulate
If equal quantities are added to equal quantities, the sums are equal.
Subtraction Postulate
If equal quantities are subtracted from equal quantities, the differences are equal.
Multiplication Postulate
If equal quantities are multiplied by equal quantities, the products are equal. (also
Doubles of equal quantities are equal.)
Division Postulate
If equal quantities are divided by equal nonzero quantities, the quotients are equal.
(also Halves of equal quantities are equal.)
Substitution Postulate
A quantity may be substituted for its equal in any expression.
Partition Postulate
The whole is equal to the sum of its parts.
A Orthogonal
Pair
Two adjacent angles that are complementary.
Perpendicular lines
two lines that intersect to form right angles.
Perpendicular line Theorem
If 2 lines are perpendicular they form congruent adjacent angles.
Skew lines
non-coplanar lines. Therefore, they
are neither parallel nor intersecting.
Parallel lines
Lines that don’t intersect and have the same distance away from each other.
Parallel line theorem
If two parallel lines are cut by a transversal, then alternate interior angles are congruent.