First look at the function

y=|x-6|,

when x>=6; (x-6) is >=0 so y=x-6

when x<6 (x-6) is negative so y=-(x-6)

but our y is 6 greater then the y we have looked at above so:

y.= x-6+6, ..when x>=6

..= -x+6+6, when x<6

or:

y.= x, ........when x>=6

..= -x+12, ..when x<6

which you should be able to sketch.

RonL