3- 8 + 4(3x + 3) +2y Thanks!!!
2 answers:
You might be interested in
Answer:
B. 4200
Step-by-step explanation:
A suitable calculator can add the terms for you. (See attached)
__
The first term is 69, and the common difference is 75-69 = 6. The general term is ...
an = a1 +d(n -1)
an = 69 +6(n -1)
Then the 28th term is ...
a28 = 69 +6(27) = 231
The average term is (a28 +a1)/2 = (231 +69)/2 = 150.
The sum is the number of terms multiplied by the average term:
sum = 28×150= 4200
