for
|a|=b, solve for
a=b and a=-b
so
|a-4|=3a-6
solve
a-4=3a-6 and a-4=-(3a-6)
first one
a-4=3a-6
minus a from both sides
-4=2a-6
add 6 to both sides
2=2a
divide by 2
1=a
other
a-4=-(3a-6)
a-4=-3a+6
add 3a both sides
4a-4=6
add 4 to both sides
4a=10
divide by 4
a=10/4
a=5/2
a=5/2 and 1
