u/Complete-Ad-9234

https://preview.redd.it/h8tmrckikxzg1.jpg?width=663&format=pjpg&auto=webp&s=a30efc09b2948d6d96e093dac0e35719f7514c49

Why would current flow upward through R1? I get the voltage divider and final equation for v1 but I just don't get this explanation even though it makes the equation work out.