mathematics!??????????????

1. (2/7)a-a=5
7[(2/7)a-a]=5(7)
2a-7a=35
-5a=35
-a=7
a=-7

2. x/5-(2x)/15=3
15[(x/5)-(2x/15)]=3(15)
3x-2x=45
x=45

3. y/6=6-(4y)/3
6(y/6)=6[6-(4y/3)]
y=36-8y
9y=36
y=4

4. 6(2(2-y)-3y)=24
6(4-2y-3y)=24
4-5y=4
-5y=0
y=0

5. (2n-5)/3=(n-10)/2
6[(2n-5)/3]=6[(n-10)/2]
2(2n-5)=3(n-10)
4n-10=3n-30
n=-20

1. (2/7)a-a=5
(2/7)a-1a=5
-(5/7)a=5
-(5/7)a/-(5/7)=5/(-5/7)
a=5* -(7/5)
a=-7

2. x/5-(2x)/15=3
15*(x/5-(2x/15)=15*3
3x-2x=45
x=45
3. y/6=6-(4y)/3
6*(y/6)=6*(6-(4y)/3)
y=36-8y
y+8y=36-8y+8y
9y=36
9y/9=36/9
y=4
4. 6(2(2-y)-3y)=24
6((2*2-2*y)-3y)=24
6(4-2y-3y)=24
6(4-5y)=24
6*4-6*5y=24
24-30y=24
24-30y-24=24-24
-30y/-30=0/-30
y=X

5. (2n-5)/3=(n-10)/2
6*(2n-5)/3=6*(n-10)/2
4n-10+30=3n-30+30
4n+20-3n=3n-3n
n+20-20=0-20
n=-20
I hope i can help you la!