First you want to distribute the 7 on the left to get:
14+35v = 3v+14.
Next subtract 3v from both sides to get
14+3v=14
Then subtract 14 from both sides
3v=0
Divide both sides by three to get
v=0.
Plugging in v=0 back into the original equation checks our work and proves v=0
14+35(0)=3(0)+14
14=14