Category: Geometry

Transforming shapes without changing their areas

Under any of Euclidean transformations—reflection, rotation, and translation, the shape of a geometric object will not change; only the position and orientation of the object will change. That is, the object and its transformation are congruent. How about when the shape can change but the area remain unchanged? Try this problem.   Problem How do you

How many squares do you see?

If you enjoyed the Facebook math problem about PEMDAS, I’m sure you will love this second math problem about counting squares which I also got from Facebook. Problem How many squares do you see? Answers given in Facebook include 24, 25, 26, 27, 38, 34, 36, 40, 42. Solution Here’s how you can systematically count the

Ratio of Areas of Regular Polygons

Problem The two regular polygons ABCDEF and JKI have the same perimeter. What is the ratio of their areas? Solution Since you are comparing areas of polygons, the most efficient solution would be to dissect them into congruent shapes. That is, show that both polygons can be tessellated or tiled by the same shape. Of