Suppose △ABC with A(0,0) , B(3,5) , and C(0,5) is rotated about side CB¯¯¯¯¯¯¯¯ . Identify the three-dimensional object formed.(1 point)

Responses

a cone with a diameter of 6 units and a height of 5 units
a cone with a diameter of 6 units and a height of 5 units

a cone with a diameter of 5 units and a height of 3 units
a cone with a diameter of 5 units and a height of 3 units

a cone with a height of 3 units and a diameter of 10 units
a cone with a height of 3 units and a diameter of 10 units

a cone with a height of 5 units and a diameter 3 units
a cone with a height of 5 units and a diameter 3 units

1 answer

To determine the three-dimensional object formed when triangle \( \triangle ABC \) is rotated about side \( \overline{CB} \), we first need to identify the dimensions of the triangle and the axis of rotation.

Given the points:

  • \( A(0,0) \)
  • \( B(3,5) \)
  • \( C(0,5) \)
  1. Identify the position of the vertices:

    • Point \( C \) is located at the top of the triangle along the vertical axis (y-axis) at \( (0,5) \).
    • Point \( B \) is located at \( (3,5) \), 3 units away from \( C \) horizontally.
    • Point \( A \) is located at \( (0,0) \) at the base of the triangle.
  2. Identify the length of the segments:

    • The length of \( \overline{CB} \) (the side along which the triangle is rotated) is \( 3 \) units (the distance from \( C \) to \( B \)).
    • The height of the triangle from \( A \) to line \( CB \) is \( 5 \) units.
  3. Determine the solid of revolution:

    • When the triangle is rotated around the vertical side \( \overline{CB} \), it creates a cone shape.
    • The height of the cone is the distance from point \( A \) to line \( CB \), which is \( 3 \) units horizontally (since \( C \) to \( B \) is horizontal and point \( A \) is directly below \( C \)) as it extends perpendicularly, creating a cone with its vertex at \( A \) and the base along the line determined by the rotation around \( \overline{CB} \).
  4. Determine the base diameter:

    • The diameter of the cone's base is equal to the distance from point \( B(3,5) \) to point \( C(0,5) \), which is \( 3 \) units on either side since point \( B \) is \( 3 \) units away from the y-axis.
    • Thus, the base radius of the cone is \( 3 \) units, giving a diameter of \( 6 \) units (as it extends \( 3 \) units to either side of the y-axis).

Therefore, the cone formed when triangle \( \triangle ABC \) is rotated about side \( \overline{CB} \) has:

  • Height: \( 3 \) units
  • Diameter: \( 6 \) units

This corresponds to the first response from the options given:

A cone with a diameter of 6 units and a height of 5 units.