I need help for a final review questions..

A ship headed due east is moving through the water at a constant speed of 6 miles per hour. However, the true course of the ship is 60 degrees. If the currents are a constant 3 miles per hour, what is the ground speed of the ship? (Round your answer to the nearest whole number.)

Question

I need help for a final review questions.. 

A ship headed due east is moving through the water at a constant speed of 6 miles per hour. However, the true course of the ship is 60 degrees. If the currents are a constant 3 miles per hour, what is the ground speed of the ship?	(Round your answer to the nearest whole number.)

anonymous · Answer

Use the Pythagorean theorem to solve for the ground speed.

$$6^{2}-3^{2}=x ^{2}$$  $$x=\pm \sqrt{27}$$$$x=\pm5.19$$ Since the speed is not negative, x=5.19

Round to nearest whole number x=5 mile per hour