(9x3)-9=18
Thisjj bf is the answer enjoy
If it took 4 miles per hour you multiply that twice cuss its traveling back then forth so you repeat the same process 30 miles times 2 which is 60 hope this helps.
If you were at 54 on the number line you would have to cross zero and go an extra 13 steps to get to -13.
So we want the difference between 54 and -13 or 54- -13 which becomes 54+13 which is 67 - that is the range