Answer:
The diver need to travel 19 meter up to reach the surface
Step-by-step explanation:
* Lets explain how to solve the problem
- For any starting point the position at it is zero
- If the moving from the starting point is vertically, then the distance
below the starting point is negative and above the starting point
is positive
- If the moving from the starting point is horizontally, then the
distance left to the starting point is negative and right to the
starting point is positive
* Lets solve the problem
- A diver is 19 meters below the surface of the water
- Assume that the surface of the water is the zero position
∵ The diver is 19 meter below the surface of the water
∴ The diver is at the position -19
- The diver need to travel 19 meters to reach the surface of the water
∵ -19 + 19 = 0
∴ The diver need to travel 19 meter up to reach the surface
, so our solutions are 
and 
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