A submarine starts at a position relative to sea level of -45 meters. The submarine then changes it's position at a rate of -6 meters per minute. What is the submarine's position after 7 minutes?
A. -3 meters
B. -44 meters
C. -58 meters
D. -87 meters
-6 * 7 = -42
-42 + (-45) = ?
To find the submarine's position after 7 minutes, we need to consider the starting position and the rate of change.
The starting position of the submarine relative to sea level is -45 meters, which means it is already 45 meters below sea level.
The rate of change given is -6 meters per minute, and since it is negative, it means the submarine is moving further below sea level at a rate of 6 meters per minute.
To find the position after 7 minutes, we need to multiply the rate of change (-6 meters/min) by the number of minutes (7).
Position after 7 minutes = -6 meters/min * 7 minutes
Calculation: -6 * 7 = -42
Therefore, the submarine's position after 7 minutes is -42 meters.
However, we started with a position relative to sea level of -45 meters (already below sea level), so we need to subtract the calculated position from the starting position.
Final position = Starting position - Position after 7 minutes
Calculation: -45 - (-42) = -45 + 42 = -3
Therefore, the submarine's final position after 7 minutes is -3 meters.
Therefore, the correct answer is A. -3 meters.