# My Geometry Dictionary

## Acute Triangle

An acute triangle is a triangle with 3 acute angles.

## Congruent

Congruent means to have the same size and shape.

## Decagon

A decagon is a polygon with 10 sides and 10 angles.

## Equilateral triangle

A equilateral triangle is a triangle with 3 congruent sides.

## Heptagon

A heptagon is a polygon with seven sides and seven angles.

## Hexagon

A hexagon is a polygon with 6 sides and 6 angles.

## Isosceles Triangle

A isosceles triangle is a triangle with 2 congruent sides.

## Nonogon

A nonogon is a polygon with 9 sides and 9 angles.

## Obtuse triangle

A obtuse triangle is a triangle with one obtuse angle.

## Octogon

An octogon is a polygon with 8 sides and 8 angles.

## Parallelogram

A parallelogram is a polygon in which opposite sides are parallel and are congruent.

## Plane Figure

A plane figure is a 2-D figure. ( flat )

## Polygon

A polygon is any shape that is closed and has 3 or more sides, no curved lines, and no lines can be crossing over each other.

A quadrilateral is a plane figure with 4 sides. (Quad means 4)

## Rectangle

A rectangle is a quadrilateral with 4 sides and 4 right angles.

## Regular Polygon

A regualr polygon is a polygon when all sides and angles are equal.

## Rhombus

A rhombus is a parallelogram and quadrilateral with congruent sides.

## Right triangle

A right triangle is s triangle with one right angle.

## Scalene Triangle

A scalene triangle is a triangle with no congruent sides.

## Trapezoid

A trapezoid is a quadrilateral with only 1 pair of parallel sides.