A boat sailing at a speed of 35mi/h set to head due west encounter a wind blowing 15mil/h due south. What is the approximate resulting speed of the boat?

Answer 1

The red dotted line is the result of the boat heading 35 mph west and the wind blowing it 15 mph south. To find the resulting speed, use the Pythagorean Theorem. 35² + 15² = speed² or speed = sqrt(35² + 15²) = 38.08 mph. The direction (which the problem is not asking for) can be found by using the inverse tangent function. Tan(θ) = 15/35 or θ = tan^-1(15/35) = 23.2° so the heading would actually be 23.2° south of west

Answer 2

Draw and label a diagram.

Use Pythagoras

s² = 15² + 35²