tar(1) xvzf /tmp/wordpress.tar.gz -C /tmp
The GNU version of the tar archiving utility
-x, --extract, --get
      extract files from an archive
-v, --verbose
      verbosely list files processed
-z, --gzip, --gunzip --ungzip
-f, --file ARCHIVE
      use archive file or device ARCHIVE
-C, --directory DIR
      change to directory DIR
source manpages: tar