INFORMATION:
We have the next figure
And we must find its surface area
STEP BY STEP EXPLANATION:
The surface area of a cone is equal to the curved surface area plus the area of the base:

Where, r denotes the radius of the base of the cone, and L denotes the slant height of the cone.
Now, we must calculate L using the right triangle formed
We can use the Pythagorean theorem,

So, having r = 9 in and L = 15 in, we can replace the values in the formula

Then, replacing π = 3.14

Finally, the surface area of the cone is 678.2 in^2
ANSWER:
678.2 in^2