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44 Cards in this Set

  • Front
  • Back
altitude of a triangle
Segment that is perpendicular from a vertex to the lince containing the opposite side
angle bisector of a triangle
Segment that bisects an angle of a triangle and has one endpoint on the opposite side
"Corresponding parts of congruent triangles are congruent"
congruent triangles
Triangles whose corresponding angles and corresponding sides are congruent
distance from a point to a line
Length of the perpendicular from the point to the line.
median of a triangle
segment that extends from a vertex to the midpoint of the opposite side
Side of a right triangle that is opposite right angle
legs of a right triangle
Sides opposite the acute angles
right triangle
triangle with one right angle
acute angle
angle whose measure is between 0 and 90
acute triangle
triangle with three acute angles
adjacent angles
two coplanar angles that have a common vertex,a common side, and no common interior points
alternate exterior angles
pair of nonadjacent angles, both exterior, on opposite sides of the transversal
alternate interior angles
pair of nonadjacent angles, both interior, on opposite sides of the transversal
union of two noncollinear rays with a common endpoint
auxiliary line
lines, segments, rays, or points added to a figure in order to facilitate a proof or an understanding of a problem
between points
Given three collinear points X, Y, and Z, Y is between X and Z if and only if XY+YZ=XZ
between rays
Given three cooplanar rays OA, OT, and OB, OT is between OA and OB if and only if: m of AOT+m of TOB=m of AOB
"If and only if" statement formed by combining a conditional and its converse into one statement
angle bisector
ray that seperates an angle into two angles of egual measures
segment bisector
any line, segment, ray, or plane that intersects a segment at its midpoint
points that lie on the same line
complementary angles
two angles whose measures sum to 90
"Then" part of a conditional statement
statement formed by joining two statements, p and q, with the words if and then
congruent angles
angles that have egual measures
congruent segments
segments having equal measures
statement related to a conditional statemtn in the form: If ~q, then ~p
statement related to a to a conditional statement in the form:If q, then p
convex polygon
polygon in which the lines containing the sides do not contain points in the polygon's interior
number paired with each point on a number line
points that lie on the same plane
theorem whose justification follows from another theorem
corresponding angles
pair of nonadjacent angles--one interior, one exterior--both on the same side of the transversal
a 10-sided polygon
deductive reasoning
reasoning logically from given statements to a desired conclusion
diagonal (of a polygon)
segment that joins two nonconsecutive vertices
absolute value of the difference of the cooridinates of two distinct points on a line
edge (plane)
line that separates a plane into two half-planes
equiangular triangle
triangle in which all angles are congruent
equilateral triangle
triangle in which all sides are congruent
formal proof
a logical argument in which each statement requires justification
hypothesis of a proof
two halves of a plane that are separated by a line