Answer: 10√17
Step-by-step explanation:
The movement of the boat takes the shape of a trapezium as shown in the attached photo.
The distance of the boat from its starting point is represented by x kilometers.
To determine the distance, x, we would apply Pythagoras theorem on the right angle triangle ABC formed. It is expressed as
Hypotenuse² = opposite side² + adjacent side². It becomes
x² = 40² + 10² = 1600 + 100
x² = 1700
x = √1700 = √100 × √17
x = 10√17
