Question

Two quick questions?

Answer 1

view attachment.

Answer 2

homework.

Answer 3

The first question is asking for \[\large\sum_{i = 1}^{15}(12i - 7) = \frac{n}{2}(a_{1} + a_{n}) = \frac{15}{2}(5 + 173) = ?\]

Answer 4

so, it's 1,335?

Answer 5

Yup.

Answer 6

Thank you very much. So the second one would I set it up the same way?

Answer 7

Pretty much. Do you understand how I got \(a_{1}\), \(a_{n}\), and \(n\)?

Answer 8

@Calcmathlete is this wrong? \[18/2 (80+201)\]