Euclidean Geometry

5 Special Lines in a Triangle

Altitude, median, and the three…

Euclidean Geometry

How to Prove the Law of Sines: a Complete Guide

When algebra meets…

Euclidean Geometry

But Why is the Total Internal Angle of a Triangle 180°?

Euclidean Geometry

The Origin of the Infamous Law of Cosines

When algebra meets…

Euclidean Geometry

Another Way to Calculate the Area of a Triangle

Besides the usual…

Euclidean Geometry

Similarity

A piece of fundamental knowledge in solving geometry…

Euclidean Geometry

2017 Canada National Olympiad Problem 4

Geometry Challenge #11

Euclidean Geometry

What’s so Special about Circumcircles?

Alright, hear me out

Euclidean Geometry

2017 Indonesia National Olympiad Problem 1

Geometry Exercise #2

Euclidean Geometry

Pythagorean Theorem

and a neat way to prove it