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Given:
Diameter of the cone, d = 18cm.
The slant height of the cone, h =23 cm.
Required:
We need to find the surface area of the cone.
Explanation:
Consider the radius formula.
[tex]r=\frac{d}{2}[/tex]Substitute d =18 in the equation.
[tex]r=\frac{18}{2}=9cm[/tex]Consider the surface area of the cone formula,
[tex]SA=\pi r(r+l)[/tex]Substitute r =9 and l =23 in the formula.
[tex]SA=\pi(9)(9+23)[/tex][tex]SA=288\pi cm^2[/tex]Final answer: