Geometry has come a long way with contributions from some of the most famous mathematicians in history.

From the earlier stages that saw the definition of basic shapes and forms, the study of measurements has advanced to a deeper understanding of most of the calculations that can reasonably relate to shapes.

Along the way, great mathematicians have made milestone contributions to this branch of mathematics, giving us ideas, formulae and other concepts that help us understand geometry better.

Geometry has also seen the emergence of some great names over time, who have defined and developed the foundations of this exciting branch of mathematics.

## Early Development of Geometry Math

Several centuries ago, somewhere between 2900BC to 1800BC, geometry was born.

The early stages were most important as the math science established concepts and theories at a fundamental level.

Over this duration, studies focused on the definition of shapes, and their direct applications, which was a very critical component of early architecture.

The most notable discovery in this age was the establishment of a way to calculate the area of a triangle. Initial geometry worked with basic shapes, with the use of circles, squares, and rectangles taking center stage. This era is the first age of geometry.

## Thales – Early Contributions to Geometry

Thales was a Greek philosopher and mathematician from Miletus, Asia Minor.

This famous Greek mathematician lived between 624 and 547 BC. He was the first person, from The Age of Mathematics, to have a mathematics concept named after him, the Thales’ Theorem.

- The diameter of a circle cuts it into half
- In an isosceles triangle, the base angles are equal
- Two triangles with one similar side and two equal angles are the same size.
- The opposite corners in an intersection of two straight lines are equal
- Thales’ theorem

Thales could rightly be considered the first real mathematician.

## Contributions by Pythagoras

This Greek mathematician lived between 570 and 495 BC.

Most of has have heard of Pythagoras when it comes to geometry. This brilliant mathematician is best known for the discovery of the Pythagorean Theorem which all children learn today in school.

Pythagoras’ Theorem states that for a right-angled triangle, the square of the hypotenuse (the longest side) is equal to the sum of the squares of the base and height (the two sides at right angles to each other).

Thise formula looks like this:

In this equation, a and b are the base and height, and c is the hypotenuse or diagonal edge of a right-angled triangle sitting on its base.

This concept was not his only significant discovery, with a few more ideas accredited to him for his diligent work in mathematics.

## Euclidian Geometry

We have all learnt about Euclidian geometry in school.

Named for its contributor Euclid who was born in Alexandria, Greece around the middle 300’s (which is mid 4^{th} century) BC.

This famous mathematician defined geometry in his era, significantly adding to the knowledge the world had about shapes, lines, and angles.

A critical aspect of his concepts was developing the understanding of the relationship between these plane figures.

For many centuries all geometry was Euclidian geometry, because all studies in this field focused on plane geometry, which significantly relied on Euclid’s theories and concepts.

## Brahmagupta – contributions circa 600AD

This famous mathematician from Rajasthan, India, was born in 598 AD.

He is a vital step in the history of geometry for his contributions to mathematics, with his most popular concept relating to the calculations regarding quadrilaterals (four-sided geometric shapes) enclosed in a circle.

Due to the nature of the forms, they’re commonly called cyclic (referring to a circle) quadrilaterals. The concepts resulting from Brahmagupta’s work also cover shapes like triangles as well, with a great deal of insight on measurements and constructions in geometry.

## Rene Descartes and Algebraic Geometry

Rene was a French mathematician who lived between 1596 and 1650.

The chief achievement in Mathematics by Rene Descartes was to establish a connection between algebra and geometry.

The two branches of mathematics had operated individually, with the sharing of logic and concepts very limited.

Descartes discovered how to figure out geometrical problems using algebra. The introduction of equations allowed for calculations in a different and simplified way, eliminating the need for conducting physical measurements for every single situation.

## Blaise Pascal

Pascal was born in Clermont-Ferrand, in June 1623. This scientist is well known for his contributions to philosophy, religion, and most importantly, mathematics.

At sixteen, he wrote his first significant work in geometry now known as Pascal’s Theorem. This theory states that if we inscribe or draw a hexagon in a circle, the three points of intersection of lines joining opposite sides of the shape lie on the same line.

This line was named the Pascal line. A brilliant mind and mathematician, he’s credited for many more contributions that paved the way for modern geometry.