what is the surface area formula for a triangular prism
The surface area of anything is the area of all the individual surfaces all added together.
Think about your triangular prism.
How many sides does it have?
What shapes are they?
Are any of the sides the same?
Find the are of each side then add them all together.
I can't' give you are formula unless you tell me the numerals (letters) that you want to use. (and what they stand for)