Tecno C9 has been proving suborn when it comes to rooting but my thanks goes to a team know as Hovatek the have come to the rescue of users of this smartphone
1. Copy the downloaded Super SU to both internal storage of your phone and SD card.
2. Extract and copy the CWM recovery.img into the same folder as the fastboot.exe and adb.exe
3. Unlock Tecno Camon C9 bootloader by following the steps here
4. Connect the phone to your PC via USB cord while switched ON and boot it into Fastboot (as instructed in the Bootloader unlock guide)
5. The moment your device enters fast boot, flash the recovery.img to the phone by typing the command below then pressing Enter fastboot
flash recovery recovery.img
6. Reboot the phone by typing the command below then pressing Enter
7. Boot the phone into recovery mode by switching off and using Volume up button + Power button
8. Once you enter recovery mode, use the volume button to move up and down
9. Scroll down to Install zip and select it
10. Select Choose zip from /storage/sdcard1
11. Navigate to the location of SuperSu.zip and select it
12. Select Yes – Install SuperSU to confirm flashing
Wait till the flashing is complete…
13. Return to the home screen (using the back option) then select Reboot
If CWM offers to fix some errors, select No.
Source Hovatek team
Now you start rocking your rooted Tecno C9 to verify that it has been rooted download and install Root Checker from google play store.