# Geometry

## 39 terms

### line segment

a straight line connecting two points

### ray

has one endpoint, but continues in the other direction forever; straight

### line

continues on in both directions forever; straight

### parallel

always the same distance apart; will never touch

### intersecting

meeting or crossing

### right angle

corner, square or 90 degrees

### equilaterial triangle

all three sides the same size

one right angle

### angle

the measurement between two lines

### vertex

point where two lines meet

### sides

lines that come together at a vertex

### triangle

3 sides, 3 vertices, 3 angles

### perimeter

the distance around a shape

4 sides, 4 vertices, 4 angles

### polygon

shapes with 3 or more sides that connects

### regular polygon

all sides the same size

5 sides

6 sides

7 sides

8 sides

9 sides

10 sides

12 sides

90 degrees

180 degrees

270 degrees

360 degrees

### symmetric

when folded along a line, both sides match

### congruent

same size and shape

### polyhedron

a 3D shape that has "many faces"

### pyramid

the base is a polygon and the faces come together in an apex

### prism

two bases are parallel to each other and are polygons

### cone

the base is a circle and the sides are curved

completely round

### cylinder

two circle bases and curved sides

### edges

where the faces of a polyhedron meet

### apex

the point at the top of a pyramid