Greg is sitting in a movie theater,

8
meters from the screen. The angle of elevation from his line of sight to the top of the screen is
11°
, and the angle of depression from his line of sight to the bottom of the screen is
51°
. Find the height of the entire screen.
Do not round any intermediate computations. Round your answer to the nearest tenth.
Note that the figure below is not drawn to scale.

5 answers

Let's assume that the height of the screen is h meters.

Since Greg is sitting 8 meters from the screen, the distance from the bottom of the screen to Greg's eye level is h + 8 meters.

From the information given, we can form two right triangles. The first triangle consists of Greg's eye level, the top of the screen, and the distance to the screen. The second triangle consists of Greg's eye level, the bottom of the screen, and the distance to the screen.

Using the tangent function, we can write the following equations:

tan(11°) = (top of screen height) / 8

tan(51°) = (bottom of screen height) / 8

Solving the first equation for the top of the screen height, we get:

(top of screen height) = 8 * tan(11°)

Simplifying, we find:

(top of screen height) ≈ 1.5058 meters

Solving the second equation for the bottom of the screen height, we get:

(bottom of screen height) = 8 * tan(51°)

Simplifying, we find:

(bottom of screen height) ≈ 11.1761 meters

The height of the entire screen is the sum of the top and bottom heights:

(total screen height) = (top of screen height) + (bottom of screen height)

Substituting the values we found, we get:

(total screen height) ≈ 1.5058 + 11.1761 ≈ 12.6819 meters

Rounding to the nearest tenth, we find that the height of the entire screen is approximately 12.7 meters.
incorrect
Apologies for the incorrect response.

Let's assume that the height of the screen is h meters.

From the given information, we have the following triangle:

1. Triangle: Greg's eye level, top of the screen, and the distance to the screen.

In this triangle, the opposite side is the height of the screen. The adjacent side is 8 meters, and the angle of elevation is 11°.

Using the tangent function, we can write the equation:

tan(11°) = h / 8

Solving for h, we get:

h = 8 * tan(11°)

Calculating this, we find:

h ≈ 1.4555 meters

Therefore, the height of the entire screen is approximately 1.5 meters.
wrong
Apologies for the mistake. Let's correct the solution.

From the given information, we have two right triangles:

1. Triangle: Greg's eye level, top of the screen, and the distance to the screen.
2. Triangle: Greg's eye level, bottom of the screen, and the distance to the screen.

Let's consider the first triangle:

In this triangle, the angle of elevation from Greg's line of sight to the top of the screen is 11°, and the distance from Greg to the screen is 8 meters.

Using the tangent function, we have:

tan(11°) = (height of the screen) / 8

Solving for the height of the screen, we get:

(height of the screen) = 8 * tan(11°)

Calculating this, we find:

(height of the screen) ≈ 1.4459 meters

Now, let's consider the second triangle:

In this triangle, the angle of depression from Greg's line of sight to the bottom of the screen is 51°, and the distance from Greg to the screen is 8 meters.

Using the tangent function, we have:

tan(51°) = (height of the screen) / 8

Solving for the height of the screen, we get:

(height of the screen) = 8 * tan(51°)

Calculating this, we find:

(height of the screen) ≈ 11.1768 meters

To find the total height of the screen, we add the heights of the top and bottom:

(total height of the screen) = (height of the screen) + (height of the screen)

(total height of the screen) ≈ 1.4459 + 11.1768 ≈ 12.6227 meters

Rounding to the nearest tenth, the height of the entire screen is approximately 12.6 meters.