Where Brainly fits
Use it to compare approaches to a problem after making your own attempt.
Check before you choose
Check the reasoning in an answer rather than copying a result without understanding it.
Find the right edition
Start with the destination for your device or the publisher's website. Use the current requirements and terms there to confirm the edition you need.
Compare the workflow
Courses, flashcards, school workspaces and library borrowing serve different needs. Canvas access depends on your school, while Libby and hoopla depend on a participating library. Check that you can access the material before comparing study features.