方程式help me!!

1. a=2
2. a=84
3. x=4
4. x=8
知道了嗎?非常簡單

1.
11a-6=8a
3a=6
a=2

2.
a/7=12
a=12*7
a=84

3.
30-(9-2x)=29
1=(9-2x)
1=9-2x
2x=8
x=4

4
3x-19=5
3x=24
x=24/3
x=8

11a-6=8a
11a-8a=6
3a=6
a=2

a/7=12
a/7x7=12x7
a=84

30-(9-2x)=29
30-9+2x=29
21+2x=29
2x=29-21
2x=8
x=4

3x-19=5
3x=5+19
3x=24
x=8

Hope can help you!!!

(1)
11a-6=8a
11a-6 6=8a 6
11a=8a 6
11a-8a=8a-8a 6
11a-8a=6
3a=6
3a/3=6/3
a=2

(2)
a/7=12
7a/7=12*7
a=84

(3)
30-(9-2x)=29
30-30-(9-2x)=29-30
-(9-2x)=-1
(9-2x)=1
9-9-2x=1-9
-2x=-8
2x=8
2x/2=8/2
x=4

(4)
3x-19=5
3x-19 19=5 19
3x=24
3x/3=24/3
x=8

1. 11a-6=8a
11-8a = 6
3a = 6
a = 2

2. a/7 = 12
a = 12 x 7
a = 84

3. 30-(9-2x) = 29
30 - 9 + 2x = 29
2x = 29 - 30 + 9
2x = 8
x = 4

4. 3x-19=5
3x = 5 + 19
3x = 24
x = 8