Corresponding Parts of Congruent Triangles are Congruent
Back
vertex of an angle
Front
Definition: two angles whose sides are opposite rays. Or straight lines.
Back
Side-Angle-Side (SAS) Postulate
Front
If 2 sides and the included angle of 1 triangle are congruent to 2 sides and the included angle of another triangle, then the 2 triangles are congruent.
Back
protractor
Front
Definition: geometry tool used to measure angles
Example: geometry tool used to measure angles
Back
straight angle
Front
formed by two opposite rays and measures 180 degrees
Back
congruent segments
Front
Definition: segments with the same length
Example: Two segments of equal length. Shown by tick marks.
Back
Linear Pair Postulate
Front
Definition: If two angles form a linear pair, then they are supplementary and adjacent!
Example: supplementary and adjacent angles
Back
angle bisector
Front
Definition: divides an angle into two congruent pieces
Example: When an object or angle is able to be divided into two even halves. If you were to take 180 degrees and divide the total by 2, you then get 90 degrees.
Back
Line
Front
Definition: a straight path extending in opposite directions with no end. Contains infinitely many points.
Example: straight path that goes in opposite directions and has an infinite number of points
Back
Converse of the Isosceles Triangle Theorem
Front
If 2 angles of a triangle are congruent, then the sides opposite those angles are congruent.
Back
bisects
Front
Definition: divides an item into two congruent pieces
Example: When a ray divides an angle into two congruent pieces.
ex. a 90 degree angle gets divided into two 45 degree angles
Back
segment
Front
part of a line the consists of two endpoints and all points in between.
Back
Plane
Front
represented by a flat surface that extends without end. Contains infinitely many lines.
Back
hypotenuse
Front
side opposite the right angle (aka the longest side)
Back
obtuse angle
Front
Definition: measures greater than 90 and less than 180 degrees
Example: An angle which measures greater than 90 degrees and less than 180 degrees
Back
isosceles triangle
Front
has at least 2 congruent sides.
Back
complementary angles
Front
two angles whose measures have a sum of 90. Each angle is called the complement of the other.
Back
Point
Front
Definition: an object that indicates location. Has no size.
Example: indicates a location that has no size
Back
vertex angle (of an isosceles triangle)
Front
Angle formed by the legs of an isosceles triangle.
Back
ray
Front
Definition: part of a line that consists of one endpoint and all points of the line on one side of the endpoint.
Example: A ray is part of a line that extends in one direction indefinitely. A light ray is a real life example.
Back
base (of an isosceles triangle)
Front
side opposite the vertex angle in an isosceles triangle.
Back
Third Angles Theorem
Front
If 2 angles of 1 triangle are congruent to 2 angles of another triangle, then the third angles are congruent.
Back
Side-Side-Side (SSS) Postulate
Front
If the 3 sides of 1 triangle are congruent to the 3 sides of another triangle, then the 2 triangles are congruent.
Back
midpoint
Front
Definition: point that bisects the segment into two congruent segments
Example: Point C is the midpoint of line segment AB.
Back
adjacent angle
Front
Definition: two coplanar angles with a common side, a common vertex, and no common interior points.
Example: 2 coplanar angles with a common side , a vertex and no common interior points
Back
included side
Front
the common side of two consecutive angles in a polygon.
Back
base angles (of an isosceles triangle)
Front
2 angles that share a base as a side.
Back
angle
Front
Definition: formed by 2 rays that share the same endpoint
Example: formed by 2 rays that share the same endpoint
Back
If a triangle is equiangular,
Front
then the triangle is equilateral.
Back
colinear
Front
Definition: on the same line
Example: on the same line
Back
complementary angles
Front
two angles whose measures have a sum of 90. Each angle is called the complement of the other.
Back
An equilateral triangle is
Front
also equiangular
Back
angle bisector
Front
A ray that divides an angle into two congruent angles.
Back
Isosceles Triangle Theorem
Front
If 2 sides of a triangle are congruent, then the angles opposite those sides are congruent.
Back
Hypotenuse Leg (HL) Theorem
Front
If the hypotenuse and a leg of 1 right triangle are congruent to the hypotenuse and a leg of another right triangle, then the triangles are congruent.
Back
right angle
Front
Definition: measures 90 degrees
Example: An example of a right angle is a angle iron
Back
Angle-Side-Angle (ASA) Postulate
Front
If 2 angles and the included side of 1 triangle are congruent to 2 angles and the included side of another triangle, then the 2 triangles are congruent.
Back
Congruent Polygons
Front
Have corresponding parts congruent.
Back
congruent angles
Front
Definition: angles that have the same measure
Example: Vertical angles
Back
acute angle
Front
Definition: angle that measures greater than 0 and less than 90 degrees
Example: its an angle that measures smaller than 90 degrees but bigger than 0 degrees
Back
vertical angles
Front
Definition: two angles whose sides are opposite rays. Or straight lines.
Example: Vertical angles are two angles whose sides are opposite rays. Or straight lines.A four way intersection.
Back
supplementary angles
Front
two angles whose measures have a sum of 180. Each angle is supplementary to the other.
Back
3 Requirements to use the HL Theorem
Front
1. There are 2 right triangles.
2. Triangles have congruent hypotenuses.
3. There is 1 pair of congruent legs.
Back
sides of an angle
Front
Definition: rays
Example: Ray AB and ray AC are the sides of the angle BAC.
Back
segment bisector
Front
a point, line, ray, or other segment that intersects a segment at its midpoint
Back
If a line bisects the vertex angle of an isosceles triangle,
Front
then the line is also perpendicular to the base.
Back
included angle
Front
an angle formed by two adjacent sides of a polygon
Back
legs
Front
congruent sides of an isosceles triangle
Back
Angle-Angle-Side (AAS or SAA) Postulate
Front
If 2 angles and a nonincluded side of 1 triangle are congruent to 2 angles and corresponding nonincluded side of another triangle, then the triangles are congruent.
Back
Plane
Front
Definition: represented by a flat surface that extends without end. Contains infinitely many lines.
Back
Section 2
(50 cards)
Theorem
Front
any statement that you can prove.
Back
Congruent Complements Theorem
Front
If two angles are complements of the same angle (or of congruent angles), then the two angles are congruent.
Back
Reflexive Property of Equality
Front
a = a
Back
Inductive Reasoning
Front
the process of reasoning that a rule or statement is true because specific cases are true.
Back
Skew Lines
Front
noncoplanar lines that are not parallel and do not intersect
Back
alternate interior angles
Front
angles that lie on opposite sides of the transversal and between the lines
Back
|| (symbol)
Front
means is parallel to
Back
Converse of the Alternate Interior Angles Theorem
Front
If 2 lines and a transversal form alternate interior angles that are congruent, then the lines are parallel.
Back
vertex of an angle
Front
endpoint where the 2 rays intersect
Back
Perpendicular Transversal Theorem
Front
In a plane, if a line is perpendicular to one of two parallel lines, then it is also perpendicular to the other.
Back
Parallel Transitivity Theorem
Front
If 2 lines are parallel to the same line, then they are parallel to each other.
Back
Deductive Reasoning
Front
the process of using logic to draw conclusions from given facts, definitions, and properties.
Back
Exterior angles of a polygon
Front
the angle formed by a side and an extension of a side
Back
Parallel Lines
Front
Coplanar lines that do not intersect.
Back
corresponding angles
Front
angles that lie on the same side of the transversal t, and the sames sides of the lines.
Back
Converse of the Same-Side Interior Angles Theorem
Front
If 2 lines and a transversal form same-side interior angles that are supplementary, then the lines are parallel.
Back
Addition Property of Equality
Front
If a = b, then a + c = b + c.
Back
Division Property of Equality
Front
If a = b, then a/c = b/c.
Back
Corresponding Angles Theorem
Front
If a transversal intersects 2 parallel lines, then corresponding angles are congruent.