Question

12+5v=2v-9

Answer 1

A couple things to keep in mind.
1) you ultimately want the unknown variable by itself on one side of the equation
2) whatever you do to one side you have to do to the other.
3) like terms can be subtracted or added
4) to get rid of a coefficient divide both sides by that coefficient

Answer 2

oh sorry 3v = -21
v= -7 because you divide by 3

Answer 3

Do you understand @momo12

Answer 4

do you get it