Answer:
8cm and 9 cm
Explanation:
Sum of sides rule:
The sum of the two smallest sides of a triangle has to be greater than the third side.
5 cm and 8 cm
One side is 5, other 8, 5 + 8 = 13. The sum has to be greater than 13, so this is not possible.
6cm and 7 cm
6 + 7 = 13, same as above, not possible.
7cm and 2 cm
7 + 2 = 9 < 13, so not possible.
8cm and 9 cm
8 + 9 = 17 > 13, so possible, and this is the answer.