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Gravity
Terms in this set (60)
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
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
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.
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
Vertex angle
The angle formed by the legs of an isosceles triangle.
slope formula
slope intercept form of a line
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.
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.
Quadrilateral
A flat shape with four straight sides. (closed)
rhombus
A quadrilateral where all sides have equal length. It is a type of parallelogram.
kite
A quadrilateral that has two pairs of sides that are equal in length but not all 4 are equal.
square
A quadrilateral where all sides have equal length, and every interior angle is a right angle (90 degrees). Special rectangle.
rectangle
A quadrilateral where all angles are right angles (90°). Also opposite sides are parallel and of equal length.
trapezoid
A quadrilateral that has a pair of opposite sides parallel.
regular polygon
A polygon is regular when all angles are equal and all sides are equal (otherwise it is "irregular").
irregular polygon
A polygon that does not have all sides equal and all angles equal.
Parallelogram
A quadrilateral with two pair of parallel sides
perpendicular lines
Lines that intersect to form right angles
adjacent angles
Two angles that share a common side and have the same vertex
coplanar
points that lie on the same plane
complementary angles
Two angles whose measures add to 90 degrees.
distance
How far it is from one point to another
ray, opposite rays
a part of a line that starts at one endpoint and extends forever
Pythagorean Theorem
In a right angled triangle: the square of the hypotenuse is equal to. the sum of the squares of the other two sides.
Chord
a straight line segment whose endpoints both lie on the circle.
Tangent
is a line that touches the circle at exactly one point, never entering the circle's interior.
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