test 1 Flashcards
Intersects a segment, line, or angle such that the two consequence parts are equal
bisector
Union of three non-collinear points together with segments that join them
triangle
Points that are all on the same line
collinear points
The union of two rays with a common endpoint
angle
Triangle such that all sides are equal
equilateral triangle
Triangle such that no two sides are equal
scalene triangle
Triangle such that exactly one angle is greater than 90 degrees
obtuse triangle
Triangle such that all angles are less than 90 degrees
acute triangle
Triangle such that one angle measures 90 degrees
right triangle
Collection of points in a straight path that continues in both directions indefinitely
line
A piece of a line with two endpoints
line segment
A quadrilateral with exactly one pair of parallel sides
trapezoid
Quadrilateral in which opposite sides are parallel
parallelogram
A parallelogram with adjacent sides equal
rhombus
A parallelogram that contains a right angle
rectangle
Rectangle with adjacent sides of equal length
square
A four sided polygon
quadrilateral
Closed geometric figure with 3 or more straight sides
polygon
All sides are of equal length
regular polygon
A common endpoint of two segments or rays
vertex
A sentence that contains a variable; when the variable is given value, then it is either true or false
open statement
A sentence that is either true or false
closed statement
To extend under or be opposite to
subtended
Line segment with endpoints on the same circle
chord
A polygon with all angles less than 180 degrees and outward facing vertices
convex
Logical operator denoted by ^
and
Logical operator denoted by ∨
or
Logical operator denoted by ~
not
Educated guess (which can be proven true or false)
conjecture
Logical operator that means “implies”
–>
The “if” and “then”. parts of a statement are switched
converse
Both parts of a statement are negated
inverse
Both parts of a statement are switched and negated
contrapositive
Polygon in which the diagonals do not intersect
concave
The exact middle of a line segment
midpoint
In a circle or triangle, a set of points whose distance to the center are less than the radius
interior to
In a circle or a triangle, a set of points whose distance to the center are more than the radius
exterior to
(n-2)*180
sum of interior formula angles
Angles that are non-adjacent, on the same side of the transversal, and one is interior while the other is exterior
corresponding angles
Share a common vertex and their sides form two lines
vertical angles
Same size and shape
congruent
Angles on the side of a figure
interior angles
Angles on the outside of a figure
exterior angles
Valid conjecture
theorem
The result of a hypothesis
conclusion
Statement assumed to be true conjecture with certain conditions
hypothesis
Statements accepted without proof
axiom
Making an inference based on premises
deductive reasoning
Tool similar to a ruler but has not measurement markings
straightedge
Tool that would collapse when lifted from a surface
floppy compass
A mathematical text authored by Euclid and his peers; the most widely circulated book about mathematics for 2000 years
elements
Objects that are side. by side and have the same distance continuously between them
parallel
A straight line at an angle of 90 to a given line, plane or surface
perpendicular
When corresponding pairs of angles have the same measure
similar
Any of a set of straight lines passing through a point
ray
A line that is this to a circle will be perpendicular to the radius of the circle at that point
tangent
An implication (contains both a hypothesis and conclusion; typically uses if-then structure)
conditional statement
When a structure has the ability to withstand outside events, such as impact or human error consequences
robust constructs
Inscribed quadrilateral whose vertices all lie on a single circle
cyclic quadrilateral
A theorem that follows very easily from another
corollary
The set of points equidistant from a given line on one side of it forms a straight line
clavius’ axiom
A deductive argument
proof
Given a line l and any point P not on l, there is exactly one line through P that is parallel to l
Hayfair’s postulate
Line segment from a vertex perpendicular to the line containing the opposite side (in a triangle)
altitude
Proof that a conjecture is false
counter example
Greek mathematics considered to be “father of geometry”
euclid
