Final answer:
A triangle is not possible if the smallest and middle numbers aren't greater than the largest number.
Step-by-step explanation:
A triangle is a three-sided figure lying on a plane with three angles that add up to 180 degrees. If the smallest and middle numbers of the triangle are not greater than the largest number, the triangle is not possible. This is because if one side is not longer than the others, it will not close the shape, and therefore, it will not form a triangle.
For example, if the sides of the triangle are represented by the numbers 3, 5, and 2, where 2 is not greater than 5, then the triangle is not possible.