A boat is heading towards a lighthouse, whose beacon-light is 139 feet above the water. The boat's crew measures the angle of elevation to the beacon, 11∘. What is the ship's horizontal distance from the lighthouse (and the shore)? Round your answer to the nearest hundredth of a foot if necessary.
Q. A boat is heading towards a lighthouse, whose beacon-light is 139 feet above the water. The boat's crew measures the angle of elevation to the beacon, 11∘. What is the ship's horizontal distance from the lighthouse (and the shore)? Round your answer to the nearest hundredth of a foot if necessary.
Use tangent function: Use the tangent function because we have the angle of elevation and the opposite side (height of the lighthouse) and we want to find the adjacent side (horizontal distance).tan(11∘)=adjacentopposite
Plug in values: Plug in the known values.tan(11∘)=adjacent139
Solve for adjacent side: Solve for the adjacent side. adjacent=tan(11°)139
Calculate adjacent side: Use a calculator to find tan(11°) and then divide 139 by this value.adjacent≈0.19438139
Find horizontal distance: Perform the division to find the horizontal distance. adjacent≈715.35
Round to nearest hundredth: Round the answer to the nearest hundredth of a foot.adjacent ≈715.35 feet