Are you trying write it into slope intercept form ?
2r + 2s = 50
2r - s = 17
-----------subtract
3s = 33
s = 11
2r - s = 17
2r - 11 = 17
2r = 28
r = 14
so r = 14 and s = 11
answer is C. r = 14, s = 11
There is no sum for this geometric series. it diverges rather than converges due to the absolute value of the common ratio (r), which is -3, being 3. for a geometric series to have a sum (to converge), the absolute value of r must be less than 1.
(you find r by dividing a2/a1, a3/a2, etc.)
hope this helps
Seven-thirty.
A half an hour past seven o'clock.
Lets use x as the number of CD's that she will buy in a month. So knowing that, our inequality can look like this. 7 + 10x < or = 100. Why? because we will have to multiply 10 with the number of CDs she will purchase in a month to get the total she spends. Hence 10 times x. She also has to add a 7 membership fee per month to this. Also, she has to remember that what she paid has to be less or equal to 100 because the problem states that she spends no more than 100 a month.