Answer:
[tex]SA=54\pi\ units^2[/tex]
Step-by-step explanation:
we know that
The surface area of the cone is given by the formula
[tex]SA=\pi r^{2}+\pi rl[/tex]
where
r is the radius of the base
l is the slant height
we have
[tex]r=3\ units\\l=15\ units[/tex]
substitute
[tex]SA=\pi (3)^{2}+\pi (3)(15)[/tex]
[tex]SA=54\pi\ units^2[/tex]