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8.7 Applications of Right Triangle Trigonometry. Some critical terminology. Horizontal any line constructed so that it is parallel with the horizon or another horizontal line. Line of Sight the line from the observer’s eye to the object
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Some critical terminology • Horizontal any line constructed so that it is parallel with the horizon or another horizontal line. • Line of Sight the line from the observer’s eye to the object • Angle of Elevation if the object being observed is above the horizontal then the angle between the line of sight and the horizontal is called the Angle of Elevation. • Angle of Depression if the object being observed is below the horizontal then the angle between the line of sight and the horizontal is called the Angle of Depression. • Angle of Inclination if the line of sight follows a physical object, such as an inclined plane or a hillside, we use the term Angle of Inclination.
Diagram of terminology. Angle of Depression Horizontal Line of Sight Horizontal Angle of Elevation
The hardest part of these story problems is drawing the picture and deciding what you are being asked to find.
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