A drone is tasked with surveying three different points in a large park. The first point (Point A) is located at (10,12) and the second point (Point B) is at (15,20) and the third point (Point C) is at (25,10). The drone needs to know the straight-line distance between these three points to determine the distance around the park. Determine the straight-line distance between Points A and B, Points B and C, and Points C and A. Then calculate the perimeter of the park. Show all your work. (3 points)

1 answer

To find the straight-line distances between the points, we can use the distance formula, which is given by:

\[ d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2} \]

where \((x_1, y_1)\) and \((x_2, y_2)\) are the coordinates of the two points.

Step 1: Calculate the distance between Points A and B.

  • Coordinates:

    • Point A = (10, 12)
    • Point B = (15, 20)
  • Using the distance formula:

\[ d_{AB} = \sqrt{(15 - 10)^2 + (20 - 12)^2} \] \[ = \sqrt{(5)^2 + (8)^2} \] \[ = \sqrt{25 + 64} \] \[ = \sqrt{89} \]

Step 2: Calculate the distance between Points B and C.

  • Coordinates:

    • Point B = (15, 20)
    • Point C = (25, 10)
  • Using the distance formula:

\[ d_{BC} = \sqrt{(25 - 15)^2 + (10 - 20)^2} \] \[ = \sqrt{(10)^2 + (-10)^2} \] \[ = \sqrt{100 + 100} \] \[ = \sqrt{200} \] \[ = 10\sqrt{2} \]

Step 3: Calculate the distance between Points C and A.

  • Coordinates:

    • Point C = (25, 10)
    • Point A = (10, 12)
  • Using the distance formula:

\[ d_{CA} = \sqrt{(10 - 25)^2 + (12 - 10)^2} \] \[ = \sqrt{(-15)^2 + (2)^2} \] \[ = \sqrt{225 + 4} \] \[ = \sqrt{229} \]

Step 4: Calculate the perimeter of the park.

The perimeter \(P\) is the sum of the lengths of all the sides formed by these distances:

\[ P = d_{AB} + d_{BC} + d_{CA} \]

Substituting the values we found:

\[ P = \sqrt{89} + 10\sqrt{2} + \sqrt{229} \]

Final Result:

The distances between the points are:

  • Distance AB = \(\sqrt{89} \approx 9.43\)
  • Distance BC = \(10\sqrt{2} \approx 14.14\)
  • Distance CA = \(\sqrt{229} \approx 15.13\)

The perimeter of the park is:

\[ P \approx 9.43 + 14.14 + 15.13 \approx 38.70 \]

Thus, the perimeter of the park, to three significant figures, is approximately:

\[ \boxed{P \approx 38.7} \]