Question

I am having trouble with this measure of a cone. I am trying to calculate the slant with the Pythagorean theorem. The measurements are a diameter of 8 and a height of 9. I keep multiplying (8 x 8) + (9 x 9) and I get 145 which I square root it to get 12.04 which equals answer d. But I know that the answer is 9.8 which I just cannot get? Please help I am not trying to cheat but to learn

Answer 1

Step-by-step explanation:

Assuming the apex of the cone is centered over the circular base, the relevant dimensions for the use of the Pythagorean theorem to find slant height are the radius (not diameter) and height.

slant height = √(4·4 +9·9) = √97 ≈ 9.8489 ≈ 9.8

Answer 2

Use the radius not the diameter

Step-by-step explanation:

We do not use the diameter, we use the radius

a^2 + b^2 = c^2

4^2 +9^2 = c^2

16+81 = c^2

97 = c^2

Take the square root of each side

sqrt(97) = sqrt(c^2)

9.848857802= c