(1500CE)

Used Roman Numerals until about

1500CE - shifting to the Arab

numerals (modern positional Base-

10 system) and Middle Eastern

thinking: Algebra, Algorithms, and

Equations.

Descartes (1650CE)

Created the Coordinate Plane

(Cartesian Coordinates, the x-y

axis, and 'graphing') by combining

Algebra Equations and Geometry

for visualizing trends in data.

- Spread use of Roman Numerals (no

Zero, no Negative), which are used

until about 1500 CE

- Math Cult

- Pythagorean Theorem

- Great Mathematician and

Geometer (formulas for Area and

Volume)

- Area of a Circle.

- Method of Exhaustion

(estimations of Area under a curve

would be the basis of Calculus

2000 years later.)

-

Base-60 counting system

(borrowed and still used in time

and degrees)

- Positional Number System

(where 91 and 19 are not the same)

- Use of 'Zero' (as a placeholder in

this system - so 9*1 is different

than 91, today that placeholder

just = 0)

al-Khwarizmi (800CE)

- Persian, wrote the book of

'Algebra'.

- Precision Measurements (Cubits)

- Early Counting Symbols and

Numbers (no Zero, no Negative)

- May have understood "pi" (built into

the Great Pyramid's dimensions?)

'The Elements' (1st Geometry

Textbook)

Eratosthenes (250 BCE)

- Measured the size (and shape!) of

the Earth