解
This Chinese character means solution.
You can watch how to write this. - (「解」の書き順（筆順）動画 - 漢字書き順辞典)
There are 3 main ways to read this, "とく (解く)" or "とける (解ける)" or "かい".
When this is combined with other Chinese characters, this is read as "かい".
"解答 (かいとう)" means answer.
"理解 (りかい)" means understand.
"分解 (ぶんかい)" means disassemble.
"謎が解ける" means "The mystery is solved."
Mystery novels are interesting.
Read it and you will become a great detective in the story.
By Higashi-Mikawa Kyōjindō Shujin (東三河狂人堂主人)