Question

The height of the cone is 12 centimeter and its slant height is 13 centimeter what is the radius of the cone
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Answer 1

Explanation,

Given,

• Height of the cone is 12 cm.
• Slant height of the cone is 13 cm.

To Find,

• The radius of the cone.

Solution,

We know that,

l² = h² + r²

Where,

• l = Slant height
• h = Height
• r = Radius

Units,

• l = cm
• h = cm
• r = cm

[ Put the values ]

⇒ 13² = 12² + r²

⇒ 169 = 144 + r²

⇒ 169 - 144 = r²

⇒ 25 = r²

⇒ r = ±√25

⇒ r = -5 cm , 5 cm

[ Note :- Ignoring negative term ]

⇒ r = 5 cm

Therefore,

The radius of the cone is 5 cm.

For information,

• Total surface area of cone is πr(l + r).
• Curved surface area of cone is πrl.
• Volume of cone is ¹/3 × πr²h.