im not really good at seventh grade math I need some help!!

Answers:
1/2a= 8
Multiply by 2/1 on both sides
1/2(2/1)a= 8(2/1)
Cross out 1/2 and 2/1 equals to a
a= 16
4n= 32
Divide by 4 for both sides
4n/4= 32/4
n= 8
3x= 36
Divide by 3 for both sides
3x/3= 36/3
x= 12
m/3= 2
Multiply by 3/1 for both sides
3/1*m/3= 2(3/1)
Cross out 3/1 and 3 becomes m
m= 6
x-8= 12
Move -8 to the other side. Sign changes from -8 to +8
x-8+8= 12+8
x= 20
48= 3k
Divide by 3 for both sides
48/3= 3k/3
k= 16
13/b= 0
Multiply by 1/13 for both sides.
13/b( 1/13)= 0(1/13)
b= 0
39= 13y
divide by 13 for both sides
39/13= 13y/13
y= 3