The 3·1 triangle contains 18° 26′ 5·82″ and the 2·1 triangle 26° 33′ 54·19″; the latter has been frequently noticed as a pyramid angle in the gallery inclinations.
Figure 32 shows these two triangles combined with the 3, 4, 5 triangle, on the circumference of a circle.
[6] 60 = 3 × 4 × 5
The 20, 21, 29 triangle contains 43° 36′ 10·15″ and the complement, 46° 23′ 49·85″.
Expressed in whole numbers—
| Radius | 29 | = | [7]12180 |
| Sine | 20 | = | 8400 |
| Co-sine | 21 | = | 8820 |
| Versed sine | 8 | = | 3360 |
| Co-versed sine | 9 | = | 3780 |
| Tangent | = | 11600 | |
| Co-tangent | = | 12789 | |
| Secant | = | 16820 | |
| Co-sec | = | 17661 |
Tangent + Secant = 2⅓ radius
Co-tan + Co-sec = 2½ radius
Sine : Versed sine :: 5 : 2
Co-sine : Co-versed sine :: 7 : 3
[7] 12180 = 20 × 21 × 29
It is noticeable that while the multiplier required to bring radius 5 and the rest into whole numbers, for the 3, 4, 5 triangle is twelve, in the 20, 21, 29 triangle it is 420, the key measure for the bases of the two main pyramids in R.B. cubits.[8]
[8] 12 = 3 × 4, and 420 = 20 × 21