# Use Trigonometric ratio to calculate Height and Distances

Line of Sight : A straight line draws from observer eye to any object that observe by observer is known as line of sight.

Angle of Elevation : angle between line of sight and horizontal line from observer eye is known as angle of elevation. Angle of Depression : if observer seeing downward then the angle between horizontal line from observer eye and line of sight is known as angle of depression. Angle of Elevation = Angle of Depression

We can use Trigonometric ratio sin , cos , tan as per requirement if height is given and you need to find distance then use tan with Angle of Elevation/depression
We know that
Sinθ = perpendicular/Hypotenuse
Cosθ = Base/ Hypotenuse
tan θ = perpendicular/Base

## How to calculate height

Example: The angle of elevation of the top of a tower at a distance of 100 meter from its foot on a horizontal plane is found to be 60 degree then find height of tower. In triangle ABC tan60 = AB/BC
tan 60=AB/100
√3=AB/100
AB(height of tower)= 100√3