Respuesta :
Answer:
- The area of a 17 in traditional TV is approximately 138.7 in².
- The area of a 17 in LCD TV is approximately 123.3 in²
- The 17 in LCD TV's screen is bigger
Explanation:
1. What is the area of a 17in traditional tv screen?
a) Measure of the diagonal = 17 in
b) The diagonal is the hypotenuse of a triangle.
c) Call x and y the length and the width of the screen. Then, by Pythagora's theorem:
- x² + y² = 17²
d) Since the ratio of the length to the width of the screen is 4:3
- x/y = 4/3
e) Solve the system of equations:
- x = 4y/3
- (4y/3)² + y² = 17²
- 16y²/9 + y² = 17²
- 16y² + 9y² = 17² × 9
- 25y² = 17² × 9
- y² = 17² × 9 / 25
- y = 17 × 3 / 5 = 10.2 in
- x = 10.2 × 4 / 3 = 13.6 in
f) Area = x × y = 10.2 in × 13.6 in = 138.72 in²
The area of a 17 inch traditional TV is approximately 138.7 in²
2. What is the area of a 17in LCD TV whose screen is in 16:9 format?
- x² + y² = 17²
- x/y = 16/9
Solve the system of equations:
- x = 16y/9
- (16y/9)² + y² = 17²
- 256y²/81 + y² = 17²
- 256y² + 81y² = 17² × 81
- 337y² = 17² × 81
- y² = 17² × 81 / 337
- y = = 8.33 in
- x = 8.33 × 16 / 9 = 14.8 in
Area = x × y = 14.8 in × 8.33 in = 123.28 in²
The area of a 17 inch LCD TV is approximately 123.3 in²
3. Which screen is bigger?
The screen of the 17 in traditional TV is bigger, because its area (approximately 138.7 in²) is greater than the area of the LCD TV (approximatle 123.3 in²).