Answer:
Step-by-step explanation:
i hope this is good enough
Answer: (B) -625
<u>Step-by-step explanation:</u>
Given the sequence {-500, -100, -20, -4, -0.8, ... }, we know that that the first term (a) is -500 and the ratio (r) is 
Input those values into the Sum formula:

X=29 and y=10
You would isolate one of the variables and then plug the expression into the other equation to find the value of one variable. Then you would plug this value into the other equation to determine the value of the remaining variable.