Calculate the slant height for the given cone. Round to the nearest tenth.

I believe so. Not 100% sure though.

11.4 is correct.

To calculate the slant height of a cone, we can use the Pythagorean theorem. The slant height (l) is the hypotenuse of a right triangle formed by the height (h) and the radius (r) of the cone.

First, we need to find the radius (r) of the cone. The diameter (d) is given as 18 cm, and we know that the radius is half the diameter. So, r = d/2 = 18/2 = 9 cm.

Next, we can use the Pythagorean theorem to find the slant height (l). The formula is: l = sqrt(r^2 + h^2), where sqrt denotes the square root.

Substituting the values, we have:
l = sqrt(9^2 + 7^2)
l = sqrt(81 + 49)
l = sqrt(130)
l ≈ 11.4 cm

The rounded answer to the nearest tenth is 11.4 cm, which corresponds to option D.