Answer: 9.8 cm
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Explanation:
Refer to the figure below.
The cone has a circle at the base which has a diameter of 8 cm. This cuts in half to 4 cm, and that's the radius. This forms the horizontal leg of the right triangle highlighted in red.
The vertical leg of the triangle is the height of the cone (9 cm).
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Use the pythagorean theorem to find the hypotenuse of the triangle, which is exactly the slant height.
a^2 + b^2 = c^2
4^2 + 9^2 = c^2
16 + 81 = c^2
97 = c^2
c^2 = 97
c = sqrt(97)
c = 9.84886
When rounding to one decimal place, we get 9.8 cm which is the final answer.
