As a navigator of this ship, you must consider the measure of the arc. Using the distance between the two lighthouses and the arc measurement, you can find the radius and center of the circle to set a reasonable distance in keeping the ship in safe waters.
First, you have to get the equation equal to 0. To do that, you need to subtract the and 48 from the right side of the equation and put it on the left side. The new equation will read