How do I solve this algebra questions,

2n+4n+4=-8, 9=5+4t, at+2=12, 2x+3=7, 3b+6=12, m/6+5=7????

2n+4n+4=-8

6n + 4 =-8
6n +4 -4 = -8-4
6n = -12
n = -2

9=5+4t
9-5 = 5 -5 + 4t
4 = 4t
4/4 = 4t/4

t = 1

2x+3=7
2x + 3 -3 = 7 -3

2x = 4
x =2

3b+6=12,
3b + 6 -6 = 12 -6
3b = 6
b =2

m/6+5=7
m/6 +5-5 = 7-5

m/6 = 2
6(m/6) = 2(6)
m = 12