Hi,
A is an arithmetic sequence
U(n)=U(n-1)+3

we needed to eliminate w, do so by diving both sides by w and obtain the above result :)
Hope this helps.
Answer:
A
Step-by-step explanation:
I don't think you have the right equation down, so this more of an educated guess than an actual direct answer
Answer:
3
Step-by-step explanation:
Your answer is 3