You list them any way you like. You can refer to them by the names of the vertices ot their ends, or you can give them any other names.
No. Angles don't have anything called a side length. However, one can use trigonometry to compute the angles of a triangle based on the side lengths of the triangle (triangles do have side lengths).
Because all side lengths are different, it must be a scalene triangle.
Only two equal side lengths
Yes and the given lengths would form an isosceles triangle.
Yes, a triangle can have side lengths of 6, 8, and 9. To determine if these lengths can form a triangle, we can apply the triangle inequality theorem, which states that the sum of the lengths of any two sides must be greater than the length of the third side. In this case, 6 + 8 > 9, 6 + 9 > 8, and 8 + 9 > 6 all hold true, confirming that a triangle can indeed be formed with these side lengths.
You can list them in any order. There is no standard.
That depends on what the side lengths are. Until the side lengths are known, the triangle can only be classified as a triangle.
If its a right angle triangle then its side lengths could be 3, 4 and 5
No. Angles don't have anything called a side length. However, one can use trigonometry to compute the angles of a triangle based on the side lengths of the triangle (triangles do have side lengths).
An isoceles triangle! It has two lengths the same!
Because all side lengths are different, it must be a scalene triangle.
That number is called the "perimeter" of the triangle.
Only two equal side lengths
A scalene triangle
A scalene triangle which has different side lengths
If you mean side lengths of 5, 4 and 1 then it is not possible to construct any triangle from the given dimensions.
A triangle with no equal side lengths is a scalene triangle.