# Geometry Symbols

Geometry is a branch of mathematics that deals with the properties of configurations of geometric objects - (straight) lines, circles and points being the most basic.

The area of mathematics that deals with space, lines, shapes and points

• Plane Geometry is about flat shapes like triangles, circles, and lines,
• Solid Geometry is about solid (3-dimensional) shapes like spheres and cubes.

## Geometry Symbol Chart

### Example

measured angle   ABC = 30º
angle formed by two rays ∠ABC = 30º
right angle = 90º α = 90º
spherical angle   AOB = 30º
´ arcminute 1º = 60´ α = 60º59′
º degree 1 turn = 360º α = 60º
´´ arcsecond 1´ = 60´´ α = 60º59’59”
$\overrightarrow{AB}$< ray line that start from point A
AB line segment the line from point A to point B
| perpendicular perpendicular lines (90º angle) AC | BC
congruent to equivalence of geometric shapes and size ∆ABC ≅∆XYZ
|| parallel parallel lines AB || CD
Δ triangle triangle shape ΔABC ≅ΔBCD
~ similarity same shapes, not the same size ∆ABC ~∆XYZ
π pi constant π = 3.141592654…

is the ratio between the circumference and diameter of a circle

c = π·d = 2·π·r
|xy| distance distance between points x and y | xy | = 5