Answer:
The submarine is at -1260 ft.
It descends 5 ft/min for 12 min.
12 min * 5 ft/min = 60 ft.
It descended 60 ft, so you must subtract 60 ft from -1260 ft.
-1260 ft + (-5)(12) ft = -1260 ft - 60 ft = -1320 ft
The error in the last line in the problem is that (-5)(12) = -60, not 60.
The correct line is:
-1260 + (-5)(12) = -1260 - 60 = -1320
Step-by-step explanation:
