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I want to install Ubuntu in dual boot with windows 8.1 in my Acer V3-572G-75CA. The partition situation is the following:
A. 600MB: recover partition
B. 300MB: system EFI partition
C. 914GB: Windows 8.1 partition
D. 15.83GB: recover partition
Of course I have to disable UEFI boot for start the Ubuntu Live USB. But then? I can create an extended partition for / and /swap, but I need to free a primary partition, isn't it? Can I delete partition A and/or B?