Trig word problem

Question

A boat is going through the water at 20 mph is heading across the river at an angle with the with the current. (the current is traveling directly east.) If the current causes a drift angle of 8 degrees, find the speed of the current.

Answer 1

Using a right triangle, specifying the hypotenuse as 20, with 8 degrees as the angle with the current, we define X=R × cos (8). So x = 20 × cos (8). This evaluates to almost 19.81 mph as the speed to the current.