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Based on Pythagorean theorem

83 237
2019-11-08

What does it mean for a polygon to be CONVEX? CONCAVE? Here, a quick class opener using 2 different approaches: https://t.co/3M17XDndq2 Why tell Ss when they can explore themselves and tell us?

18 36
2019-10-31

Regular dodecagon - Dissection into 15 rhombs

6 12
2019-10-18

Dissection of square to regular hexagon

62 241
2019-10-02

Pentagonal pyramid and inscribed dodecahedron

24 78
2019-10-01

Have you ever wondered why there are 360 degrees in a circle? The reason goes back more than 4000 years, to ancient Babylon. 🔄 https://t.co/FCsuZhdt4H

11 14
2019-09-24

Dividing an equilateral triangle into four equal areas

5 42
2019-09-17

sin(2v) = 2*sin(v)*cos(v): Dynamic & modifiable illustration using equal areas. For a quick investigation for Ss (w/o ID appearing at the end): https://t.co/hIaGZcseR3.

65 150
2019-09-09