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From point A and B on level ground, the angle of elevation of the top of a building are 25° and 37°. |AB| = 57m. Calculate the distance of the top of the building from A and B if they are both on the same side of the building.

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Final answer:

To find the distances from points A and B to the top of the building with given angles of elevation, we use tangent functions and solve a system of two equations. We calculate the height of the building first and then use it to find the distances from A and B to the top using the tangent of their respective angles.

Step-by-step explanation:

To calculate the distance from point A and point B to the top of the building with the given angles of elevation, we will use trigonometric functions, specifically the tangent. Since the problem involves two right triangles sharing a common height, we can set up two equations using the tangent of the angles of elevation from points A and B. The Pythagorean theorem is also relevant here for understanding the relationship between the sides of a right triangle but is not directly used for this calculation.


Let h be the height of the building, dA the distance from A to the base of the building, and dB the distance from B to the base of the building. From point A, the angle of elevation is 25°, which means Τan(25°) = h/dA. Similarly, from point B, Τan(37°) = h/dB.


The distance |AB| = 57m, so dA + dB = 57m. These are two equations with two unknowns, which can be solved simultaneously. Once we find h, we can then find the distances from points A and B to the top of the building by using the original tangent ratios.


Steps for Calculation

  1. Write down the two tangent equations.
  2. Express one variable in terms of the other using the known distance between points A and B.
  3. Solve the system of equations to find the height of the building.
  4. Use the height to calculate the distance from A and B to the top of the building.

User Narine Poghosyan
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