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Gravity
Terms in this set (51)
Collinear
Points that lie on the same line
Linear Pair
A pair of adjacent angles whose noncommon sides are opposite rays.
Supplementary angles
Two angles whose sum is 180 degrees
Complementary angles
Two angles whose sum is 90 degrees
Vertical Angles
A pair of opposite congruent angles formed by intersecting lines
Angle addition postulate
If P is in the interior of <RST, then m<RSP + m<PST = m<RST
Segment addition postulate
If B is between A and C, then AB + BC = AC
Congruent
Having the same size and shape
Angle bisector
a ray that divides an angle into two congruent angles
Segment bisector
a segment, ray, line, or plane that intersects a segment at its midpoint
Midpoint
A point that divides a segment into two congruent segments
postulate
something accepted as true without proof; an axiom
theorem
A mathematical statement which we can prove to be true
inductive reasoning
A type of logic in which generalizations are based on a large number of specific observations.
Emphasis on experimentation and scientific method
deductive reasoning
reasoning in which a conclusion is reached by stating a general principle and then applying that principle to a specific case (The sun rises every morning; therefore, the sun will rise on Tuesday morning.)
parallel lines
lines in the same plane that never intersect
conditional statements
A statement that can be written in if-then form.
hypothesis
A testable prediction, often implied by a theory
An educated guess
conclusion
A summary based on evidence or facts
triangle sum theorem
The sum of the measures of the interior angles of a triangle is 180 degrees
Transitive property
If a=b and b=c, then a=c
Substitution property
If a=b, then a can be substituted for b in any equation or expression
Line segment
A part of a line with two endpoints
Line
1. A long thin mark on a surface. 2. A continuous extent of length, straight or curved, without breadth or thickness; the trace of a moving point. 3. Long, narrow mark or band.
converse of a conditional statement
When the hypothesis and conclusion are switched. The converse of p ➝ q is q ➝ p.
A statement formed by interchanging the hypothesis and the conclusion in a conditional statement.
transversal
a line that intersects two or more coplanar lines at different points
corresponding angles
Angles formed by a transversal cutting through 2 or more lines that are in the same relative position.
same side interior angles
two interior angles on the same side of the transversal
same side exterior angles
two exterior angles on the same side of the transversal
alternate interior angles
angles between 2 lines and on opposite sides of a transversal
alternate exterior angles
Angles that lie outside a pair of lines and on opposite sides of a transversal.
Acute triangle
A triangle that contains only angles that are less than 90 degrees.
Obtuse triangle
A triangle with one angle that is greater than 90 degrees.
Right triangle
a triangle with one right angle
Isosceles triangle
a triangle with at least two congruent sides
Equilateral triangle
A triangle with three congruent sides
Regular triangle
All congruent sides and angles
Scalene triangle
a triangle with no congruent sides
Base angles
Two angles that have the base as a side.
Vertex angle
The angle formed by the legs of an isosceles triangle.
Point slope equation of a line
y-y1=m(x-x1)
slope formula
y2-y1/x2-x1
slope intercept form of a line
y=mx + b (m is the slope, b is the y intercept point)
y-intercept
The point where the graph crosses the y-axis
altitude of a triangle
the perpendicular segment from a vertex to the opposite side or to the line that contains the opposite side
perpendicular bisector of a triangle
A line that is perpendicular to a segment at its midpoint.
SAS postulate
If two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the triangles are congruent.
SSS postulate
If three sides of one triangle are congruent to three sides of another triangle, then the triangles are congruent.
ASA postulate
If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent.
AAS postulate
If two angles and a non-included side of one triangle are congruent to two angles and a non-included side of another, then the two triangles are congruent.
HL Postulate
If a hypotenuse and leg of one right triangle are congruent to the corresponding hypotenuse and leg of a second right triangle, then the triangles are congruent.
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