What letter is used as a mathematical symbol in geometry?

Answer 1

Some examples:

a for area,

b for breadth,

c for circle or curve,

d for diameter or depth or dimension,

f for foci,

l for length or line,

m for modulus (= slope),

r for radius,

v for volume,

w for width,

x for horizontal coordinate,

y for vertical coordinate,

z for third orthogonal coordinate in 3-d geometry.

and finally, pi for the ratio of the circumference of a circle to its diameter.