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line segment

can be measured because it has 2 endpoints

congruent

when segments have the same measure

segment bisector

any segment, line, or plane that intersects a segment at its midpoint

perpendicular

lines, segments, or rays that form right angles

undefined terms

terms only explained using examples and descriptions

ex: point, line, plane

ex: point, line, plane

point

a location

line

made up of points and has no thickness or width

collinear

points on the same line

plane

flat surface made up of points

coplanar

points that lie on the same plane

space

a boundless, 3D set of all points

contains lines and planes

contains lines and planes

precision

depends on the smallest unit available on the measuring tool

between

for any 2 points A and B on a line, there is another point C between A and B

constructions

methods of creating geometric figures without the benefit of measuring tools

absolute error

the absolute value of the difference between the actual measure of an object and the allowable measure

relative error

the ratio of the absolute error to the actual measure

significant digits

represent the accuracy of a measurement

midpoint

the point on the segment that divides the segment into 2 congruent segments

degree

a unit of measure used in measuring angles and arcs

ray

part of a line

opposite rays

if you choose a point on a line, that point determines exactly 2 rays

angle

formed by 2 noncollinear rays that have a common endpoint

sides

the rays of the angle

vertex

the common endpoint

interior

inside an angle

exterior

outside an angle

right angle

90 degrees

acute angle

less than 90 degrees

obtuse angle

larger than 90 degrees

angle bisector

a ray that divides an angle into 2 congruent angles

adjacent angles

2 angles that lie in the same plane, have a common vertex and a common side, but no common interior points

vertical angles

2 nonadjacent angles formed by 2 intersecting lines

linear pair

a pair of adjacent angles with noncommon sides that are opposite rays

complementary angles

2 angles with measures that have a sum of 90

supplementary angles

2 angles with measures that have a sum of 180

n-gon

a polygon with n sides

regular polygon

a convex polygon in which all the sides are congruent and all the angles are congruent

perimeter

the sum of the length of the sides of the polygon

circumference

the distance around the circle

area

the # of the square units needed to cover a surface

polyhedron

a solid with all flar surfaces that enclose a single region of space

face

each flat surface (polygon)

edges

the line segments where the faces intersect

prism

a polyhedron with 2 parallel congruent faces

bases

2 parallel congruent faces

regular prism

a prism with bases that are regular polygons

pyramid

a polyhedron with all faces except for one intersecting at one vertex

regular polyhedron

a polyhedron if all its faces are regular congruent polygon and all of the edges are congruent

platonic solids

5 types of regular polyhedra

cylinder

a solid with congruent circular bases in a pair of parallel

cone

a circular base and a vertex

sphere

a set of points in space that are a given distance from a given point

surface area

the sum of the areas of each face of a solid

volume

the measure of the amount of space the solid encloses

orthographic drawing

the 2D views of the top, left, front, and right sides of an object

net

a pattern for a 3D solid