# hpatss Geometry Ch 1

## 51 terms

### line

a straight, continuous arrangement ofg infinitely many points

### plane

a flat surface that has no thickness and extends infinitely along its length and width

### point

represented by a dot ...it has no size, only location

on the same line

### coplanar

on the same plane

### line segment

consists of two endpoints of the segment and all of the points between them that are collinear with the two points

### end points

the two points that define the limits of a line segment

### congruent

two geometric structures that have the same measure or length

### midpoint

a point on the segment that is the same distance from both endpoints

### bisects

divides the segment into two congruent segments or an angle into two congruent angles

### ray

begins at a point and extends in a straight line...aka a half line

### angle

formed by two rays that share a common endpoint called a vertex

### vertex

common endpoint of two rays that form an angle

### measurement of an angle

the smallest amount of rotation about the vertex from one ray to the other...measured in degrees

### parallel lines

lines in the same plane that never intersect each other

### perpendicular lines

lines that intersect with each other at 90 degrees

### skew lines

lines that are noncoplanar and also do not intersect

### right angle

an angle that measures 90 degrees

### acute angle

an angle that measures less than 90 degrees

### obtuse angle

an angle that measures more than 90 degrees

### pair of vertical angles

formed by two intersecting lines that share a vertex but no common sides

### linear pair of angles

two angles that share a vertex and a common side and their non-common sides form a line

### complementary angles

two angles whose measurements add up to 90 degrees

### supplementary angles

two angles whose measurements add up to 180 degrees

### polygon

a closed figure in a plane formed by connecting line segments endpoint to endpoint with each segment intersecting exactly two others

### polygon diagonal

a line segment that connects two nonconsecutive vertices

### convex polygon

no diagonal is outside the polygon

### concave polygon

at least one diagonal is outside the polygon

### equilateral polygon

all sides of the polygon are equal length

### equiangular polygon

all angles of the polygon are equal measures

### reguylar polygon

a polygon that is both equilateral & equiangular

### right triangle

a triangle that has one right angle

### acute triangle

a triangle that has three acute angles

### obtuse triangle

a triangle with one obtuse angle

### scalene triangle

a triangle with no congruent sides

### equilateral triangle

a triangle with three congruent sides

### isosceles triangle

a triangle with 2 congruent sides

### trapezoid

a quadrilateral with exactly one pair of parallel sides

### kite

a quadrilateral with two distinct pairs of consecutive congruent sides

### parallelgram

a quadrilateral with two pairs of parallel sides

### rhombus

an equilateral parallelogram

### rectangle

a parallelogram with four congruent angles

### square

an equilateral rectangle

### circle

the set of all points in a plane at a given distance from a center point in the plane

a segment from the center to a point on the edge of the circle

### diameter

a segment containing the center with endpoints on the circle

### arc of a circle

two points on the circle and the continuous part of the circle between the two points

### semicircle

an arc of a circle whose endpoints are the endpoints of a diameter

### minor arc

arc of a circle that is smaller than a semicircle

### major arc

arc of a circle that is larger than a semicircle

### arc measure

determined by measuring the central angle (vertex is the center point of the circle)