I need help on this one, please!

Option B,14.6 cm and D,20.3 cm

Step-by-step explanation:

Let a and b represent the lengths of the two known sides such that a≥b. Let c represent the length of the unknown side, the length of c must fall within  

a−b<c<a+b

11.9-9.1<c<11.9+9.1

2.8<21

By elimination,

Option B and D remain, i.e 14.6 cm & 20.3 cm

hello i am doing good for you that it's summer in your country or state ; )

btw in my country we just have sun and rain as (because i live in the caribbean lol)

also, thx a lot for the points : )