Answer:
Net force = 509.90 N
Step-by-step explanation:
Given that,
Force exerted by wind is 500 N South on a sailboat.
The force exerted by water is 100 N on the sailboat.
Two forces are acting at an angle of 90 degrees. We can find the net force acting on the sailboat. Let it is F.

So, the net force on the sailboat is 509.90 N.