chapter 1 terms and defintions
Point: A point has no dimension. It’s represented by a dot.
Line : A line has one dimension. It’s represented by a line with two
arrowheads, but it extends without end AB. Through any two
points, there is exactly one line.
Plane (1.1) A plane has two dimensions. Through any three noncollinear
points, there is exactly one plane
Collinear points (1.1) Points that lie on the same line.
Coplanar (1.1) Points that lie on the same plane.
Segment (1.1) A segment is part of a line that consists of two endpoints and
all points in between. AB
Ray (1.1) A ray is part of a line consists of one endpoint and all other
points on the line on one side of the endpoint. AB
Opposite Rays (1.1) Two rays that share the same endpoint and form a line.
Intersection (1.1) Two or more geometric figures intersect if the have on or
more points in common.
Ruler Postulate (1.2) Every point on a line can be paired with a real number. This
makes a one-to-one correspondence between the points on
the line and the real numbers. The real numbers that
corresponds to that point is called the coordinate of the
point.
Distance (1.2) The distance between AB is written as the absolute value of
the difference of the coordinates of A and B
Segment addition
postulate (1.2)
If three points A, B, and C are collinear and B is between A
and C, then AB + BC = AC
Congruent Segments (1.2) Segment that have the same length ≅
Midpoint (1.3) The midpoint of a segment is a point that divides the segment
into two ≅ segments
Midpoint Formula in a
Coordinate Plane (1.3)
Given AB where A(x1, y1) and B(x2, y2) the midpoint M of AB
is M(
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Segment Bisector (1.3) A point, line, ray, or segment that cuts another segment in
half at the midpoint.
H. Chapter 1 Vocabulary Name_________________________________Period__________
Distance Formula (1.3) The distance formula between to points A(x1, y1) and B(x2, y2)
is d = (x2 − x1)
2 + (y2 − y1)
2
Angle (1.4) An angle that is formed by two rays with the same endpoint.
Sides (1.4) The rays of an angle.
Vertex (1.4) The endpoint of an angle.
Acute Angle (1.4) An angle less than 90 degrees
Right Angle (1.4) An angle that is exactly 90 degrees
Obtuse Angle (1.4) An angle that is greater that 90 degrees and less than 180
degrees
Straight Angle (1.4) An angle that is exactly 180 degrees.
Angle Addition Postulate
(1.4)
If a point is in the interior of an angle and two angles share a
common side at point, then the measure of the two smaller
angles will sum up to the bigger angle.
Complementary Angles
(1.5)
Two angles whose measures have a sum of 90 degrees. Each
angle is called a compliment.
Supplementary Angles
(1.5)
Two angles whose measures have a sum of 180 degrees. Each
angle is called a supplement.
Adjacent Angles (1.5) Angles that share a common side
Linear Pair (1.5) Two adjacent angles whose uncommon sides are opposite
rays.