# Math terms chapter 7 geometry

## 25 terms

### Polygon

A closed figure made up of lines segments.

### Vertex

A point where 2 or more sides meet.

### Interior angle

An angle formed on the inside of a polygon by 2 sides meeting at a vertex.

### Exterior angle

An angle formed on the outside of a geometric shape by extending 1 of the sides passed a vertex.

### Ray

A part of a line with 1 end point.

### Equiangular

Having all angles equal

### Bisect

Divide into 2 equal parts.

### Right bisector

A line perpendicular to a line segment and passing through its mid point.

### Centroid

The point where the medians of a triangle intersect.

### Similar

Having all corresponding sides proportional.

### Regular polygon

A polygon with all sides equal and all interior angles equal.

### Mid point

The point that divides the line segments into 2 equal segments.

### Median

The line segement joining a vertex of a triangle to the mid point of the opposite side.

Ajoining or next to.

### Transversal

Line intersecting 2 or more lines.

### Congruent

Equal in all respects.

### Convex polygon

A polygon with no part of any line segment joining 2 points on the polygon outside.
All the interior messure less than 180 degrees.

### Concave polygon

A polygon with parts of some line segments joining on the polygon outside the polygon.
Can have angles greater than 180 degrees.

### Pentagon

A polygon with 5 sides.

### Hexagon

A polygon with 6 sides.

### Heptagon

A polygon with 7 sides

### Octagon

A polygon with 8 sides.

### Decagon

A polygon with 10 sides.

### Dodecagon

A polygon with 12 sides