# Geometry Flashcards

## Created by aburling

### Square

4 equal sides. 90 degree angles.

4-sided polygon

### Perimeter

distance around a figure

### Area

number of square units it takes to cover a figure

### Base

bottom of a figure

### Height

the line that makes a 90 degree angle with the base

90 degree angle

3-sided polygon

### Acute Triangle

3-sided polygon, each angle is less than 90 degrees

### Obtuse triangle

3-sided polygon, 1 angle greater than 90 degrees

### Right Triangle

3-sided polygon. One 90 degree angle.

### Isosceles Triangle

3-sided polygon. 2 congruent sides.

### Equilateral Triangle

3-sided polygon. 3 congruent sides. 3 60 degree angles.

### Scalene Triangle

3-sided polygon. No congruent sides

### Leg

the 2 sides that make the right angle in a right triangle

### Hypotenuse

side opposite the right angle in a right triangle

### hypotenuse

side opposite the right angle in a right triangle

### parallelogram

4-sided quadrilateral. 2 pairs of parallel lines

### parallel lines

lines that will never intersect

### trapezoid

4-sided quadrilateral. 1 pair of parallel lines

### congruent

same size, same shape

### rhombus

4 equal-sided polygon

### segment

line between two points

### vertex or vericies

the point where 2 lines meet

### polygon

many-sided figure, closed, straight line segment

### regular polygon

polygon with congruent sides and congruent angles

### irregular polygon

polygon without all congruent sides

### straight angle

angle measuring 180 degrees

### circle

infinite set of points equidistant from a centerpoint

half the diameter

### diameter

distance across a circle through the center point

### pi

ratio of circumference of a circle to its diameter, irrational; = 3.14

### circumference

distance around a circle

half of a circle

### inscribed

a figure drawn inside another

### circumscribed

a figure drawn within a circle

### complementary angles

angles whose sum equals 90 degrees

### Supplementary angles

angles whose sum equals 180 degrees

### interior angle

angles inside of a polygon

### exterior angle

angle made when you extend one of the sides of the polygon outside from the polygon

### regular polygon

a polygon with congruent sides and congruent angles

5-sided polygon

6-sided polygon

7-sided polygon

8-sided polygon

9-sided polygon

### Flickr Creative Commons Images

Some images used in this set are licensed under the Creative Commons through Flickr.com. Click to see the original works with their full license.