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Gravity
Terms in this set (31)
Geometry
word composed of two Greek terms, "geos" meaning earth and "metros" meaning to measure
Euclidean Geometry
identifies a geometry which Euclid formalized and which was adapted for our use
Undefined terms
terms in Euclidean geometry which mathematicians consider only described
Point
one of the undefined terms; it has only position and has no lenth, width or thickness; it is represented by a dot
Line
one of the undefined terms; it is composed of an infinite series of points; it has length but no width or thickness and extends without limit in two directions
Plane
one of the undefined terms; it has length and width but has no thickness; it is usually represented by a parallelogram
Postulate
a statement that is accepted as fact
Theorem
a statement which has been proven
Segment
a part of a line with endpoints
Ray
a part of a line which has one endpoint and the other end extends without limit
Opposite rays
two rays which have the same endpoint and which extend in opposite directions
Congruent segments
segments which have the same length
Distance
the length of a segment between two points or its endpoints
Distance formula
on a number line, D = |a-b|;
in a coordinate, D =
Midpoint
the point in the center of a segment
Midpoint formula
on a number line, M = (a+b)/2;
in a coordinate plane, M =
Compass
tool used to draw rays and circles
Protractor
tool used to measure angles
Straightedge
tool used to draw straight line segments
Angle
figure formed by two segments or rays with a common end point
Vertex
the point formed when two segments or rays intersect iin an angle
Acute angle
an angle with a measure greater than 0 degrees and less than 90 degrees
Obtuse angle
an angle with a measure greater than 90 degrees and less than 180 degrees
Right angle
an angle whose measures is 90 degrees
Straight angle
an angle whose measure is 180 degrees
Reflex angle
an angle whose measure is greater than 180 degrees and less than 360 degrees
Linear pair
two angles who share a common vertex and whose exterior sides form a straight angle
Complementary angles
two angles whose sum equals 90 degrees
Supplementary angles
two angles whose sum equals 180 degrees
Adjacent angles
two angles who share a common side and vertex and do not overlap their interior space
Vertical angles
two angles created by intersecting lines, segments, or rays who share a common vertex, are "opposite" to each other, and have the same degree measure
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