The absolute value equation that represents the situation with the points marked is attached
Graphing the absolute value equation that represents the situation
From the question, we have the following parameters that can be used in our computation:
The above function is an absolute value equation that has a vertex of (250, 50)
The horizontal distance from the left shore where the river bottom is 20 feet below the surface is calculated by setting d to 20
So, we have
This gives
Expand
|s - 250| = 150
Expand and evaluate
s - 250 = 150 and s - 250 = -150
This gives
s = 250 + 150 and s = 250 - 150
Evaluate
s = 400 and s = 100
The points are marked on the graph