Unlock or decrypt your FileVault-encrypted boot drive from the command line on macOS Mojave

As part of working with FileVault on macOS Mojave, it may be necessary to decrypt an encrypted boot drive in order to fix a problem. On Mojave all boot volumes will use Apple File System (APFS), so to unlock or decrypt an encrypted boot drive from the command line, you will need to do the following:

1. Identify the relevant encrypted APFS volume
2. Unlock the encrypted APFS volume
3. If needed, decrypt the encrypted APFS volume

For more details, see below the jump.