Final answer:
The answer to the question cannot be determined without further information.
Step-by-step explanation:
A line integral over a triangle can be evaluated directly by using the appropriate method, such as the line integral formula or Green's theorem. However, without a specific equation or context, it is not possible to determine whether the line integral can be evaluated directly or not. Therefore, the answer to the question 'evaluate line integral directly triangle' cannot be determined without further information.