The height is the vertical length from the vertex to the bottom surface, from which the hypotenuse can be calculated.

Let's look at it from another angle:

The angle between the connecting line from the O point to the top corner of the bottom edge and the bottom edge is half of 60 degrees, that is, 30 degrees.

Its right angle is a/2.

So the length of the line is a divided by the root number 3.

Then take the hypotenuse as a.

You can get the square root of the height of a/3 times 6, and the bottom of the front view is a/2.

It can be seen that the hypotenuse of the front view is 1/6 times of the root number 33.

The circumference is a+a/3 times of the root number 33.