Answer:
4
Step-by-step explanation:
6+8=14 and so the other side would be 4 because when you add them all together its 18
It is 4cm
If the perimeter is 18, and with the two sides given (8 and 6) you would do 8+6 to get 14 then find the difference between 14 and 18, and that is 4.
