 | Term | Definition |
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Collinear points |
Points that lie on the same line |
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Coplanar points |
Points that lie on the same plane |
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Line segment |
Part of a line that consists of two points, called endpoints, and all points on the line that are between the endpoints |
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Ray |
Part of a line that consists of a point, called an initial point, and all points on the line that extend in one direction |
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Opposite Rays |
Rays with a common endpoint that lie on the same line and extend in opposite directions |
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Intersection |
The set of points that two or more geometric figures have in common |
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Coordinate |
The real number that corresponds to a point on a line |
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Segment Addition Postulate |
If B is between A and C, then AB + BC = AC. If AB + BC = AC, then B is between A and C |
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Pythagorean Theorem |
In a right triangle, the square of the length of the hyptenuse is equal to the sum of the squares of the lengths of the legs, . |
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Congruent Segments |
Segments that have the same length |
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Angle |
Consists of two different rays that have the same initial point. The rays are the sides of the angle, and the initial point is the vertex of the angle. |
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Congruent Angles |
Angles that have the same measure |
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Protractor Postulate |
Consider a point A on one side of line . The rays of the form can be matched one to one with the real numbers from 0 to 180. The measure of , , is equal to the absolute value of the difference between the real numbers for ray and . |
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Interior of angle |
Points that lie between the points that lie on each side of the angle |
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Exterior of angle |
Points that are not in the interior of an angle |
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Angle Addition Postulate |
If P is in the interior of , then . |
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Acute angle |
Angle whose measure is less than 90° |
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Right angle |
Angle whose measure is 90° |
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Obtuse angle |
Angle whose measure is greater than 90°, but less than 180° |
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Straight angle |
Angle whose measure is 180° |
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Midpoint |
The point that divides, or bisects, a segment into two congruent segments |
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Segment Bisector |
A segment, ray, line, or plane that intersects a segment at its midpoint |
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Vertical angles |
Two angles whose sides form two pairs of opposite rays |
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Linear pair |
Two adjacent angles whose non-common sides form a line |
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Complementary angles |
Two angles whose sum of their measures is 90° |
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Supplementary angles |
Two angles whose sum of their measures is 180° |
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Conditional statement |
A type of logic statement that has two parts: a hypothesis and conclusion |
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Inverse |
The statement formed when you negate the hypothesis and conclusion of a conditional |
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Converse |
The statement formed by switching the hypothesis and conclusion of a conditional statement |
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Contrapositive |
The statement formed when you negate the hypothesis and conclusion of the converse of a conditional statement |
