# Chapter 9 pre algebra geometry

### 53 terms by juliettesibley

#### Study  only

Flashcards Flashcards

Scatter Scatter

Scatter Scatter

## Create a new folder

### Circumference

Distance around circle

### Diameter

A chord that passes through the center of the circle

Segment that has one endpoint at the center and the other point on the circle

### Circle

The set of all points in a plane that are the same distance apart

### Alternate interior angles

Non-adjecent interior angles that lie on the same side of the transversal

### Corresponding angles

lie on the same side of the transversal and are in corresponding positions

### Plane

flat surface with no thickness that contains many lines and extends without end in the direction of all its lines

ABCD

### Point

location in space with no size

### Line

series of points that extends in opposite directions with no end
<-> <->
AB BA

### Line segment

Part of a line with 2 endpoints

___ ___
PQ QP

### Ray

Part of a line that has exactly one endpoint

<->
CR

### Parallel

Two lines that lie in the same plane and dont intersect

### Skew

Lines that are in the same plane and dont intersect and aren't parallel

### Acute

less than 90º angle

### Obtuse

Greater than 90º and less than 180º

90º angle

### Straight angle

equal to 180º
straight line

Share and vertex and a side but no common points

### Vertical

formed by two intersecting lines and are opposite

### Congruent

Angles that have the same measure

### Supplementary

sum of two angles is 180º

### Complementary

sum of two angles is 90º

### Transversal

Lines that intersect two other lines in different points

### Corresponding

Lie on the same side of the transversal and corresponding

### Polygon

closed plane figure with at least three sides that only meet at their endpoint

### Triangle

three sided polygon

3 acute angles

1 right angle

1 obtuse angle

### Equilateral

3 congruent sides

### Isosceles triangle

2 congruent sides

### Scalene triangle

no congruent sides

4 sides

### Trapezoid

At least one pair of parallel sides

### Paralellogram

both pairs of opposite sides are parallel

### Rhombus

four congruent sides

four 90º angles

### square

four 90º angles and four congruent sides

### Regular polygon

all sides and angles congruent

5

6

7

8

9

10

### Chord

segment whose endpoints are in a circle

c=πd
c=πr2

c=circumference
d=diameter
2=2x
π=pi

### Central angle

angle whose vertex is the center of a circle
360º in a circle

### Perpendicular lines

lines, segments, or rays that intersect to form right angles

### segment bisector

lines, segments, or rays that divides a segment into two congruent segments

### perpendicular bisector

lines, segments, or rays that is perpendicular to the segment in bisects

### Angle bisector

ray that divides an angle into two congruent angles

3.1415....etc
π

Example: