Nexus 7 Root
Nexus 7 is a phone that's released earlier than Nexus 6p, don't get fooled by those numbers guys.
Step 1: Get your phone prepared with bootloader, SuperSU (2.65 or earlier), and TWRP
Step 2: On computer, do the command that get you flashed into the adb bootloader (this is after turning on the USB debug mode and unlock your phone)
Step 3: On phone, enter recovery mode (volume down + start)
Step 4: Flash TWRP into your phone
Step 5: Enter TWRP and install SuperSU
There is also a varience of models: N900A and N9005, both can use this guide
If needed, I will expand this guide for better explaination
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