Question

The Pyraminx is a Rubik's cube-type toy in the shape of a tetrahedron. The Pyraminx shown below has edges 15\,\text{cm}15cm long and vertical height h=12.2\,\text{cm}h=12.2cm. The triangle drawn with dashed lines is a right triangle. What is the distance rr?

Answer 1

8.727

Explanation:

Since the below edge, d = 15 cm, and the height, h = 12.2 cm, we will use the Pythagorean theorem to find the distance r.

`d^2=r^2+h^2`

`(15)^2 = r^2+(12.2)^2`

`r^2 = (15)^2-(12.2)^2=225-148.84=76.16`

`r=√(76.16)=8.727`