geometry part one
when three or more lines intersect at one point
concurrent
the perpendicular segment from a vertex to the line containing the side opposite that vertex.
altitude
a segment that has its endpoints at a vertex of a triangle and the midpoint of the opposite side
the point at which three lines intersect
point of concurrency
the point of concurrency of the medians of a triangle
centroid of a triangle
the point of concurrency of the angle bisectors of the triangle
incenter of a triangle
the point of concurrency of the lines containing the altitudes of the triangle
orthocenter
when the vertex of an angle is on the circle and the sides of angle are chords of the circle.
inscribed
when a point from two objects is the same distance from the objects.
equidistant
the point of concurrency of the perpendicular bisectors of the sides of the triangles.
circumcenter
a circle that contains the three vertices of the triangle
circumscribed
negating both the hypothesis and conclusion of a conditional
inverse
a convincing argument that uses deductive reasoning and can be written in many forms
proof
when a statement has the opposite meaning of another statement.
negation
an accepted statement of fact
postulate
a geometric figure made with only a straight edge and a compass
construction
when you negate and reverse the hypothesis and the conclusion of a conditional
contrapositive
an if-then statement that relates to the hypothesis
conditional
a law of logic that states that if a conditional statement and hypothesis are true, then its conclusion is also true
law of detachment
a law of logic that states that given two true conditionals with the conclusion of the first being the hypothesis of the second, there exists a third true conditional
this table lists all the possible combinations for two or more statesments.
truth table
a line, segment, or ray that is perpendicular to the segment and divides the segment into two equal parts.
perpendicular bisector
is the result of a single trial in a probability experiment
outcome
an arc that is smaller then a semicircle
minor arc
a polygon with eight sides