# What is the formula for the slant height of a cone in terms of its radius r and a height h?

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The formula for the slant height of a cone has to be determined. The radius of the base is r and the height of the cone is h.

Take a vertical cross-section of the cone through the top. This gives a right triangle with the radius of the base r and the height h being the dimensions of the smaller sides. The hypotenuse is the slant height. This is equal to `sqrt(r^2 + h^2)`

**The formula for the slant height of a cone is **`sqrt(r^2+h^2)`