The first problem, all you need to do is combine like terms then isolate the n:
4n-2n=4
~subtract 2n from 4n (2n)
2n=4
~then divide both sides of the equation by 2 to isolate the n
n=4
The second problem follows the same steps of combining like terms and isolating the variable. Here, you'll have to combine 2 like terms:
-12=2+5v+2v
~first combine the variables which is just 5v+2v which is 7v
-12=2+7v
~then subtract 2 from both sides to isolate the 7v
-14=7v
~then divide both sides by 7 to isolate the v and get your answer
-2=v
Hope that helped!
