Question

Arithmetic sequence and series algebra 2

Find S10 for 2+5+8+...
And

Find S10 for -1+-7+-13+-19+...

Answer 1

1: 29 2: -55

Step-by-step explanation:

1: ... 8, 11, 14, 17, 20, 23, 26, 29 ...

2: ... -19, -25, -31, -37, -43, -49, -55 ...

1: Find S10 for 2+5+8...

first number: 2

Common Difference: 3

nth number to obtain: 10

2: Find S10 for -1+-7+-13+-19...

First number: -1

Common Difference: -6

nth number to obtain: 10