The distance between point A and point B is 12.

So |a-b|= 12

When 1. Both a and b are on the left side of the origin.

a & lt0，b & lt0

So |a|=-a, |b|=-b

So -a=-4b.

a=4b

So | a-b | = | 4b-b | = | 3b| = 3 | b | =-3b =12.

b=-4，a=4b=- 16

When 2A, b and b are on the right side of the origin.

a & gt0，b & gt0

So |a|=a, |b|=b

So a=4b.

a=4b

So | a-b | = | 4b-b | = | 3b | = 3 | b | = 3b =12.

b=4，a=4b= 16

1.a is on the left side of the origin and b is on the right side of the origin.

a & lt0，b & gt0

So |a|=-a, |b|=b

So -a=4b.

a=-4b

So | a-b | = |-4b-b | = |-5b | = 5 | b | = 5b =12.

b= 12/5，a=-4b=-48/5

2a is on the right of the origin, and b is on the left of the origin.

a & gt0，b & lt0

So |a|=a, |b|=-b

So a=-4b.

So | a-b | = |-4b-b | = |-5b | = 5 | b | =-5b =12.

b=- 12/5，a=-4b=48/5

|a-3|+|2b-8|+|c-2|=0

The absolute value is greater than or equal to 0, and the sum is equal to 0. If one is greater than 0, at least one is less than 0, which is invalid.

So all three are equal to 0.

So a-3 = 0, 2b-8 = 0 and c-2 = 0.

a=3，b=4，c=2

So a+3b-2c

=3+ 12-4

= 1 1