Answer:
The two bases of a rectangular prism are rectangles, while the two bases of a triangular prism are triangles.
Explanation:
Any prism has two bases. Since we are talking about a rectangular prism and a triangular prism both must have two bases.
For example, a square prism has two bases and they are both square.
In this case a rectangular prism has two bases that are rectangles and a triangular prism also has two bases and both bases are triangles.
Note: For the figure to have only one base it must be called a pyramid.
Thus, the answer is:
The two bases of a rectangular prism are rectangles, while the two bases of a triangular prism are triangles