Step 1: Analyse the given data.

Key words to understand the question.

- A line joining the eye of the observer and object viewed by the observer. This line is called
**“line of sight”. ** - The line of sight is above the horizontal line and angle between the line of sight and the horizontal line is called
**angle of elevation**. - The line of sight is below the horizontal line and angle between the line of sight and the horizontal line is called
**angle of depression**.

Step 2: When we want to solve the problems of heights and distances, we should consider the following:

- All the objects such as towers, trees, buildings, ships, mountains etc. shall be considered as linear for mathematical convenience.
- The angle of elevation or angle of depression is considered with reference to the horizontal line.
- The height of the observer is neglected, if it is not given in the problem.

Step 3: According to the given data make a imaginary figure.

GIVEN: A large balloon has been tied with a rope and it is floating in the air.

Angle of elevation \theta_1

Angle of depression \theta_2

The height of the building is h feet.

Skill 1; First make a building(DE) of height h and Assume a balloon with a

rope(AC) floating in the air.

Skill 2: Draw a horizontal line (DB) from the top of the building to the balloon.

Skill 3: Make a angle of elevation and angle of depression from the top of the

building