Question

Jules is aboard a submarine studying marine life. She’s trying to find a family of whales and must time when the submarine descends perfectly to find them. Her submarine is 22 feet below sea level and descends at a constant rate of 12 ft. per minute. The submarine must stay no less than 400 ft. below sea level. Let m = the number of minutes. Write an inequality that can be used to find how long the submarine can descend. Then, write the time the submarine can descend.

Answer 1

Answer:

32.33 <= m

Step-by-step explanation:

Since we are dealing with below sea level our initial starting point and max level will both be negative values, while our descending rate will also be negative because we are going down. Using the values provided we can create the following inequality...

-400 <= -12m - 12

Now we can solve the inequality to find the max number of minutes that the submarine can descend.

-400 <= -12m - 12   ... add 12 on both sides

-388 <= -12m   ... divide both sides by -12

32.33 <= m