Answer:
C.

Explanation:
Let w be the number of weeks.
We have been given that you decide to save an additional $85 per week, so the money saved in w weeks will be equal to 85w.
We are also told that you have already saved $350. This means that the total money saved in w weeks will be
.
Since you need at least $715 to go on a trip to Arizona. This means that the total money saved in w weeks should be greater than or equal to 715. We can represent this information in an equality as:

Therefore, the inequality
shows the number of weeks, w, you need to save to be able to go on the trip and option C is the correct choice.