Geometry 9- Honors Finals

supplementary angles

2 angles whose sum is 180 degrees

right angle

an angle that measures 90 degrees

straight angle

an angle that measures 180 degrees, essentially forming a straight line

linear pair

a pair of adjacent angles that are supplementary

vertical angles

a pair of opposite CONGRUENT angles formed by intersecting lines

complementary angles

a pair of angles whose sum is equal to 90 degrees

inscribed angles

formed by two chords that share an endpoint on the circle, starts on the edge of the circle and is reflected across the circle

central angle

an angle whose vertex is the center of the circle

angle bisector

a line/line segment that divides an angle into two congruent halves

segment bisector

a segment, ray, line, or plane that intersects a segment at its midpoint

parallel

lines that never intersect

perpendicular

Intersecting at or forming right angles

skew

lines that are neither parallel nor intersecting

Transversal

a line that intersects two or more lines

chord

a straight-line segment who intersects the circle at 2 points

radius

The distance from the center of a circle to any point on the edge

secant

a LINE that intersects a curve at a minimum of two points

tangent

a line touching the circles/ellipses at only one point

collinear

two or more points lying in the same straight line

coplanar

points lying or acting in the same plane

polyhedron

a three-dimensional object with flat faces that are all polygons

platonic

only ONE type of polygon used as faces

isosceles trapezoid

a specific type of trapezoid where the two non-parallel sides (legs) are equal in length

rhombus

A parallelogram with four congruent sides, an equiangular quadrilateral

parallelogram

a four-sided flat shape (quadrilateral) where opposite sides are both parallel and equal in length

kite

a quadrilateral with two pairs of adjacent sides congruent and no opposite sides congruent

square

A quadrilateral with 4 sides that are equal and has all 90 degree angles

concave

a shape that bends inward at some point, forming a "cave-like" indentation

convex

a shape that does not have a line jutting inward, or just a regular shape

interior angles

angles on the inside of parallel lines cut by a transversal

exterior angles

the angles formed between the side of the polygon and the extended adjacent side of the polygon (or just the outside of a shape)

regular polygon

a polygon that is both equilateral and equiangular

Medians

a line segment that connects an angle of the triangle to the midpoint of the side opposite the angle

midsegment

literally the midpoint guys come on you know this smh

altitude

the height of a shape

perpendicular bisector

a line that intersects a line segment at its midpoint and forms a right angle (90 degrees) with that segment

circumcenter

point where THREE perpendicular bisects meet

centroid

intersection of the medians (ALWAYS INTERIOR)

Orthocenter

The point of concurrency of the altitudes of a triangle

incenter

the point of concurrency of the angle bisectors of a triangle

what is a postulate

a statement that is accepted as true WITHOUT proof

what's a theorem

a general proposition NOT self-evident but proved by a chain of reasoning

converse

the statement formed by exchanging the hypothesis and conclusion of a conditional statement

inverse

negative sentence, the opposite or the reverse of something else

Biconditional

a statement that contains the words "if and only if"