How best to answer this.....

I tried to answer this and just got myself into a muddle. I think instead, that I will quote from one of my Feng Shui books.

"The positive and negative qualities of Yin and Yang are expressed as either a solid line (Yang) or a broken line (Yin). These lines taken three at a time, provide eight possible combinations of Yin and Yang which are known as the eight Trigrams."

"Each of the eight ancient Trigrams has a specific meaning ranging from Ch'ien, which consists of three unbroken lines and symbolizes Yang, the father or head of the household, through to three broken lines, K'un, which symbolizes Yin and Mother Earth."

These 8 trigrams are also the basis for the I Ching. They are combined with one another to form the 64 hexagrams of the I Ching.

I hope this helps.....??

Hui li

BTW, the book I was quoting from is:
Feng Shui by Steven Skinner
Published by Parragon