The re-size of your '/home' will depend on where you laid the original partition on your hdd. If you have additional free space on the hdd you could create a new '/home' with this space and then mount your '/home/your_users' singular on the new '/home'. Meaning you would create a mount point for each user on the new '/home' then mount each user to that mount point. Or just 'mv /your_Old_home_device/your_users /home' to the new '/home'. Then use the open available space on the 'old_home' as you wish.
That way you would not have to re-size each partition after '/home' that you might have.
Another possible solution would be to add another hdd with a new '/home' partition with usable space to use as your new expanded '/home'. You would then copy or move your_user files space to the new '/home'.
BTW, if you happen to have a 'KNOPPIX
' LiveCD then you will have parted available to you for use for the partition work.
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'. More than just SlackwareŽ links!