Thales, Theorem, and Geometry

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If AC is a diameter, then the angle at B is a right angle (Thales)

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I met Thales in a coffee shop. He was busy scribbling on paper. I went to him. He was surprised to see me. Without being invited to sit down, I had first sat down in a chair. We were facing each other.

I ordered coffee. Thales did not respond to my presence, as if I was not in front of him. Whereas he had been surprised to see me. I realized that I was a troublemaker in their community.

I caught a glimpse of the scrawled paper. I saw a few triangles and numbers and letters. I've heard of the theorem he once brought before the scientists.

"Geometry that will change the future!" I tried to get his attention. Apparently he turned towards me. I smiled triumphantly.

"What do you know about geometry?" Thales asked.

Geometry is a branch of mathematics concerned with questions of shape, size, relative position of figures, and the properties of space.^[1] In simple language, Geometry is all about shapes and their properties.^[2] I said with confidence. He nodded.

"Is that one of your theorems?" I asked, pointing to his paper.

He showed simple triangle in a circle.

On the triangle with one of its ribs through the center of the circle (in other words the diameter of the circle), the angle in front of the rib is always equal to 90 °. Since OA, OB and OC are the same length (circular radius), then triangles AOB and BOC must be equilateral triangles, thus and Given the number of triangular angles equal to 180 °, then:

^[3]

This time I was nodding. Actually I did not understand what he said. Thales was so eager to explain his theorem to me. But this was really magical.

"I have to go!" Thales said. "You can reflect on what I explained earlier. I do not have time to explain in detail this theorem. I'm running out of time. I have to go back. The Greeks need me." Suddenly he disappeared.

I did not like geometry. To me, geometry was very boring because it consists of endless numbers, axioms, definitions, propositions and architectural evidence from time to time quite confusing.

But all my conjecture was wrong. Geometry was a very important branch of mathematics!

Geometry is everywhere. Angles, shapes, lines, line segments, curves, and other aspects of geometry are every single place you look, even on this page. Letters themselves are constructed of lines, line segments, and curves! Take a minute and look around the room you are in, take note of the curves, angles, lines and other aspects which create your environment. Notice that some are two-dimensional shapes while others are three-dimensional shapes.^[4]

Without geometry, life was simply an unformed space. Forms required accurate calculations and figures. They formed intricate patterns but so simple when we mastered geometry. Thales had paved the way. Now our task is to develop it.

Geometry has many practical uses in everyday life, such as measuring circumference, area and volume, when you need to build or create something. Geometric shapes also play an important role in common recreational activities, such as video games, sports, quilting and food design. Without geometry, engineers and architects wouldn't be able to design and construct houses, buildings, cars and tools that make life easier and more enjoyable.^[5]

That's how geometry works. It connects from one point to another and calculates accurate angles.

I saw Thales's scribbled paper he had left on the table. I picked it up and folded it. At the top of the paper, I wrote: Thales, Theorem, and Geometry. []

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References

_{[1] https://en.wikipedia.org/wiki/Geometry
[2] https://www.mathsisfun.com/geometry/
[3] https://paradoks77.blogspot.co.id/2011/05/pembuktian-teorema-thales.html
[4] https://www.universalclass.com/articles/math/geometry/why-is-geometry-important.htm
[5] https://sciencing.com/geometry-used-real-life-8698204.html}

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