The answer is 6 I had this problem on my test..It was correct..
65.625
Step-by-step explanation:
Answer:
D. 11655
Step-by-step explanation:
First find the 90th term:
a90=a1+(n−1)d
= -4+89(3)=263
Then find the sum:
Sn = n(a1 + an) / 2
S90 = 90 (-4 + 263) /2
S90 = 23,310/2
<u>S90 = 11,655</u>
<span> 2-4r = - 18
</span><span> 2-2-4r = - 18 -2
-4r = -20
r = 5</span>
