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The height of a house subtends a right a...

The height of a house subtends a right angle at the opposite street light. The angle of elevation of light from the base of the house is `60^(@)`. If the width of the road be 6 meters, then the height of the house is

A

`8sqrt(3)` m

B

8 m

C

6 m

D

`6sqrt(3)`m

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AI Generated Solution

The correct Answer is:
To solve the problem step by step, we will use trigonometric ratios and the information provided in the question. ### Step-by-Step Solution: 1. **Understand the Problem**: - We have a house and a street light. The height of the house subtends a right angle at the street light. The angle of elevation from the base of the house to the top of the street light is \(60^\circ\). The width of the road is 6 meters. 2. **Define Variables**: - Let \(h_1\) be the height of the house. - Let \(h_2\) be the height of the street light. 3. **Use the Angle of Elevation**: - From the base of the house, the angle of elevation to the street light is \(60^\circ\). - Using the tangent function: \[ \tan(60^\circ) = \frac{h_2}{6} \] - We know that \(\tan(60^\circ) = \sqrt{3}\), so: \[ \sqrt{3} = \frac{h_2}{6} \] 4. **Solve for \(h_2\)**: - Rearranging the equation gives: \[ h_2 = 6 \cdot \sqrt{3} \] 5. **Consider the Right Triangle**: - The height of the house \(h_1\) can be expressed in terms of \(h_2\) and the height above the house: \[ h_1 - h_2 = \text{height of the house above the street light} \] 6. **Use the Right Triangle with Angle \(30^\circ\)**: - The angle of elevation from the top of the house to the street light is \(30^\circ\) (since \(90^\circ - 60^\circ = 30^\circ\)). - Using the tangent function again: \[ \tan(30^\circ) = \frac{6}{h_1 - h_2} \] - We know that \(\tan(30^\circ) = \frac{1}{\sqrt{3}}\), so: \[ \frac{1}{\sqrt{3}} = \frac{6}{h_1 - h_2} \] 7. **Solve for \(h_1 - h_2\)**: - Rearranging gives: \[ h_1 - h_2 = 6 \sqrt{3} \] 8. **Substitute \(h_2\) into the Equation**: - We already found \(h_2 = 6 \sqrt{3}\), so substituting gives: \[ h_1 - 6\sqrt{3} = 6\sqrt{3} \] 9. **Solve for \(h_1\)**: - Adding \(6\sqrt{3}\) to both sides gives: \[ h_1 = 6\sqrt{3} + 6\sqrt{3} = 12\sqrt{3} \] 10. **Final Result**: - Therefore, the height of the house \(h_1\) is: \[ h_1 = 12\sqrt{3} \text{ meters} \]
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