Cannot delete partition in Windows 10

Windows Disk Manager is not able to manage linux partition type like ext or swap. To manage these partitions try to use software like EaseUS Partition Master or GParted.

Personally i prefer GParted because it can be use as live CD/USB and no need any installation.

Boot on GParted

1. Download GParted here.
2. Create a live USB using software like Rufus.
3. Reboot on bios to select USB drive for the next boot.

Using GParted

Note : in GParted modifications are not effective until you press Apply button

At first boot you will see a window like :

Right click on partition you want to delete. When you delete a partiton, memory become unallocated. When memory is unallocated you wan use Resize/Move feature on Windows partition to extand it.

Apply settings using Apply button and reboot to Windows.