After diving 86 feet below the surface, a diver ascends at 4 feet per minute. after 12 minutes pass, where is the diver located in relation to the surface? include how you solve the question, it'll be very appreciated thnx guys ^ ^

One possible way:
-86+(4*12)=-38
-86 is the number where the diver is. 86 feet below the surface.
4*12 is the total number of feet he has ascended in 12 minutes.
Because he is ascending, so you add 4*12 (or 48) to -86.
The answer is -38, meaning he's 38 feet below the surface.

The diver is now 38 feet below the surface.

Hope this helps.

Maybe the answer is 20mm. all i really did was just multiply, which is obvious.