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90 terms

includes points, lines, rays, angles, polygons, triangles, quadrilaterals, circles

point

has no size, only location

line

straight, continous arrangement of infinitely many points; has no thickness; one-dimensional

plane

flat surface; two-dimensional; surface extends indinitely along its length and width; a plane is named with script capital letter

collinear

points that lie along the same line

coplainar

points that lie within the same plane

line segment

consists of two points called the endpoints of the segment and all the points between them that are collinear with the two points

congruent segments

segments that are equal in measure or length

midpoint

the point on the segment that is the same distance from both endpoints. A pair of hatch marks refer to line segments being the same length

bisects-

to cut in half

ray

begins at a point and extends infinitely in one direction

angle

formed by two rays that share a common endpoint

vertex

the common endpoint of the two rays of the angle

sides

the rays of an angle

measure of an angle

the smallest amount of rotation about the vertex from one ray to the other

degrees

unit of measurement for an angle

protractor

a geometry tool used to measure angles

congruent angles-

angles that are equal in measure

angle bisector

a ray that divides the angle into two congruent angles

parallel lines

lines that do not intersect and are part of the same plane

perpendicular lines

lines that do intersect and form a right angle

skew lines

lines that are neither parallel nor do they intersect (for 3-D setting)

right angle

an angle that measures 90 degrees

acute angle

an angle that measures less than 90 degrees

obtuse angle

an angle that measures more that 90 degrees

pair of vertical angles

angles that are formed by two intersecting lines; they share a common vertex but not a common side

linear pair of angles

two angles are a ____if they share a vertex and a common side and their non-common sides form a line

complementary angles

angles that form a right angle

supplementary angles

angles that sum up to 180 degrees

polygon

closed figure in a plane, formed by connecting line segments endpoint to endpoint with each segment intersecting the other

consecutive vertices

vertices that are adjacent to one another

consecutive angles

angles that are adjacent to one another

diangonal

a line segment that connects any two nonconsecutive vertices

concave polygon

a polygon that has at least one diagonal on the outside

convex polygon

a polygon that has no diagonals on the outside

congruent polygons

polygons that have exactly the same size and shape

equilateral polygons

a polygon who's sides are all equal

equilangular polygon

a polygon whose angles are all equal

regular polygon

a polygon whose sides and angles are all equal

triangle

3 sides

quadrilateral

4 sides

pentagon

5 sides

hexagon

6 sides

heptagon

7 sides

octagon

8 sides

nonagon

9 sides

decagon

10 sides

enneagon

11 sides

dodecagon

12 sides

triskaidecagon

13 sides

tetrakaidecagon

14 sides

pentakaidecagon

15 sides

hexakaidecagon

16 sides

heptakaidecagon

17 sides

octakaidecagon

18 sides

nonakaidecagon

19 sides

icosagon

20 sides

icosakaihenadecagon

21 sides

triacontagon

30 sides

hectagon

100 sides

chiliagon

1000 sides (chilagon?)

myriagon

10000 sides

acute triangle

all angles are less than 90 degrees

obtuse triangle

one angle is more than 90 degrees and less than 180 degrees of a three sided polygon

right triangle

one angle is exactly 90 degrees

scalene triangle

no two sides are congruent of a three sided polygon

isosceles triangle

at least two sides are congruent of a three sided polygon

equilateral triangle

all sides are congruent of a three sided polygon

trapazoid

a quadrilateral with exactly one pair of parallel sides

isosceles trapazoid

top and bottom are parallel, two sides are congruent, top two angles are congruent, bottom two angles are congruent

right trapazoid

two right angles

kite

a quadrilateral with two pairs of consecutive congruent sides. The diagonails are perpendicular

parallelogram

a quadrilateral with two pairs of parallel sides

rhombus

an equilateral parallelogram

rectangle

a parallelogram with four congruent angles (right angles); an equilateral parallelogram

square

an equilateral, equilangular parallelogram; a regular quadrilateral; an equalateral rectangle

circle

a set of all points in a plane that are the same distance from a given point (center) in a plane

radius

a line segment from the center point of a circle to a point on the edge of a circle

diameter

a line segment passing through the center point of a circle and whose endpoints are on the edge of the circle

chord

any line segment whose endpoints are on the edge of a circle; the diameter is the longest chord

congruent circles

circles that have the same radius length

concentric circles

circles that share the same center point

arc of a circle

the continuous (unbroken) part of a circle that is in between two points on the edge of a circle

semicircle

arc of a circle whose endpoints are the endpoints of the diameter

minor arc

an arc of a circle that is smaller than a semicircle

major arc

an arc of a circle that is larger than a semicircle

arc measure

the measure of the central angle (in degrees)

central angle

angle formed by two radii and whose vertex is the center point of a circle

tangent

a line that intersects the circle at exactly one point

secant

a line that intersects the circle at exactly two points

inscribe angle

angle whose vertex is the point on a circle; the sides of this angle are the chords of the circle