Answer:
8 cm and 9 cm
Explanation:
The rule for these types of problems is that the sum of the 2 shorter sides in a triangle is greater than the biggest side's length. If you think about it, it does seem sensible.
5+8 and 6+7 are both 13, but they aren't greater than the biggest side's length which is also 13.
7+2 is also wrong as it is 9, which is less than 13.
8+9= 17, and 17 is greater than 13.
So that's the answer.
Hope this helps! :)