我們知道菱形三十面體可以被分割成20塊菱形六面體，而且其中10塊還能組成菱形二十面體。現在我們想要將菱形九十面體做分割。我們先利用正多面體製造出特殊的菱形多面體，像是菱形十二面體、菱形二十面體……，再對這些菱形多面體做分割。藉由觀察這些多面體分割時的規律，我們發現有兩種方法能夠有系統地去分割菱形九十面體。
1.因為菱形多面體一定會是環帶多面體，所以我們可以藉由環帶多面體的性質將菱形九十面體切割成一個較小的菱形多面體，並重複使用相同的技巧將菱形九十面分割成120塊菱形六面體。
2.藉由菱形九十面體的表面，將菱形九十面體分割成多種我們孰悉的菱形多面體，再去分割這些較小的菱形多面體，最後也能將菱形九十面體分割成120塊菱形六面體。
我們使用Cabri 3D來完成我們的作圖。

We know that a rhombic triacontahedron can be dissected into 20 rhombohedra, and 10 of them constitute a rhombic icosahedron. Now, we want to dissect a rhombic enneacontahedron. We first use Platonic solid to create some special rhombic polyhedra, such as rhombic dodecahedron, rhombic icosahedron…, and then we dissect these rhombic polyhedra into rhombohedra. By observing the regularity of the dissections, we find that there are two ways to systematically divide the rhombic enneacontahedron.
1.Since any rhombic polyhedron is also a zonohedron, we can use the property of zonohedron to dissect the rhombic enneacontahedron into a smaller rhombic polyhedron. Therefore, we use the same technique repeatedly to dissect the rhombic enneacontahedron into 120 rhombohedra.
2.Depending on the faces of the rhombic enneacontahedron, we can divide it into many kinds of rhombohedral polyhedron which we are familiar with, and then dissect all the smaller rhombic polyhedra into rhombohedra. Finally, we still can the same result that a rhombic enneacontahedron can be dissected into 120 rhombohedra.
We use Cabri 3D to accomplish our graphs.

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[8] https://en.wikipedia.org/wiki/Golden_rhombus
[9] https://en.wikipedia.org/wiki/Rhombohedron
[10] https://en.wikipedia.org/wiki/Trigonal_trapezohedron