49 terms

# Geom Ch. 1 - Introducing Geometry

#### Terms in this set (...)

Acute Angle
Angle measuring less than 90 degrees
Obtuse Angle
Angle measuring more than 90 degrees
Right Angle
Angle measuring exactly 90 degrees
parallelogram
a quadrilateral with opposite sides parallell
Trapezoid
a quadrilateral with exactly one pair of parallel sides
collinear
lying on the same line
coplanar
lying on the same plane
point, line, plane
Building blocks of Geometry, undefined terms
line segment
two points (the endpoints) all the points between them that are on the line containg them.
congruent segment
segments that have the same measure
midpoint
a point ON a line segment that is equally distant from both endpoints.
ray
all points on a line that lie on one side of a point (the ray's endpoint).
congruent angles
angles that have the same measure
angle
formed by two rays that share an endpoint so long as they do not overlap
angle bisector
a ray that shares the vertex of the angle and divides the angle into two congruent angles.
degrees
the unit in which angles are measured
Vertical Angles
formed by intersecting lines and do not share a common/adjacent side.
Linear Pair of Angles
a pair of angles that share a side and their non-shared side form a straight line (they are supplementary)
supplementary angles
two angles whose sum is 180 degrees
complimentary angles
two angles whose sum is 90 degrees
polygon
closed figure in a plane, formed by connecting line segmenst endpoint to endpoint with each segment intersecting exactly two others.
diagonal
a line segment that connects two NON-consecutive vertices
congruent polygons
polygons that have exactly the same size and shape.
equilateral polygon
polygon that has all equal sides
equiangular polygon
polygon that has all equal angles
regular polygon
polygon that has all equal angles AND sides
right triangle
a triangle with exactly one right angle
actue triangle
a triangle with all angles less than 90 degrees
obtuse triangle
a triangle with exactly one obtuse angle
scalene triangle
a triangle with no equal sides
equilateral triangle
a triangle with all equal sides
isosceles triangle
a triangle with two OR MORE equal sides
rhombus
a parallelogram with equal sides
square
a parallelogram with equal angles and sides. (a regular quadrilateral)
kite
a quadrilateral that has two pair of distinct, consecutive congruent sides
circle
set of all points in a PLANE that are a give distance from a given point
diameter (of a circle)
a line segment containing the center of a circle, with endpoints that lie on the circle
a segment from the center of a circle to a point on the circle.
concentric circles
circles that share a center
congruent circles
circles that have the same radius
semicircle
an arc of a circle whose endpoints are on the diameter
minor arc
an arc that is smaller than a semicircle (name with 2 letters)
major arc
an arc that is larger than a semicircle (name with 3 letters)
central angle
an angle whose vertex is at the center of a circle
chord
a segment with both of its endpoints on the circle
tangent
a line that intersects a circle exactly once
Point of tangency
point where a tangent line intersects a circle
measure of an arc
equivalent to the measure of it's central angle
space
set of all points