If you’ve paid attention in geometry class, solving the puzzle in the video below shouldn’t be difficult. For those who cannot go beyond figuring the angles that form this unusually shaped star, here’s a video by Presh Talwalkar from the YouTube channel, Mind Your Decisions.

What is the measure of angle A in degrees? Your options: (A) 20 (B) 30 (C) 35 (D) 40 (E) 45.

Talwalkar points out that the puzzle was a tricky one for 200,000 US students in the year 1999. About 75% of the students failed to get it right.

Comparing triangles to other triangles and drawing tangents to circles might not have been a popular subject for many students. Some grow up to find the subject so abstract that their daily lives are unaffected by geometry.

If you also feel that there’s no value in studying triangles and see if they’re congruent or not, here’s an interesting video that can change that perspective – and it involves movies.

YouTube channel Now You See It explores how cinematographers and directors subtly use triangles, circles and shapes to portray cute, evil and boring characters, and thereby manipulate emotions.


And as for Euclid, known as the father of geometry, this video of drawings, although made for children, can make you forget the complex theories and enjoy the illustrations to understand how geometry came into existence.