To find the height of the cone, we can use the Pythagorean theorem. In a right triangle formed by the radius, the height, and the slant height of the cone, the slant height is the hypotenuse, and the radius and height are the other two sides.
Given:
- Diameter of the cone = 18
- Radius (r) = Diameter / 2 = 18 / 2 = 9
- Slant height (c) = 15
Let's denote:
- Height of the cone = h
According to the Pythagorean theorem: \[ c^2 = r^2 + h^2 \]
Substituting the known values: \[ 15^2 = 9^2 + h^2 \] \[ 225 = 81 + h^2 \]
Now, solve for \( h^2 \): \[ h^2 = 225 - 81 \] \[ h^2 = 144 \]
Taking the square root of both sides: \[ h = \sqrt{144} = 12 \]
So, the height of the cone is 12.
To summarize: (a) The height of the cone is 12.
If you have any further questions or if (b) refers to something else, please let me know!