Question

The diameter of the base of a right cone is 6 cm. If the total surface area of the cone is 90π cm^2, what is the length of the slant height?

a.) 6.6 cm.
b.) 9 cm.
c.) 21 cm.
d.) 27 cm.

Could I have the formula to solve this problem?

Answer 1

You need the formula for the total area of a cone.

Here it is:

\(\Large SA_{cone} = \pi r^2 + \pi r s\)

Answer 2

SA = (Area of Base) + (Area of cone)

Answer 3

Where
r = radius
s = slant height

Answer 4

I just repeated what mathstudent said.

Answer 5

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Answer 6

From the diameter, you can find the radius.
You have the total surface area, so the only unknown in the formula is s, the slant height.
You can solve for it.