(40 points) i need some . an answer definition is appreciated as well.

-9

Step-by-step explanation:

We are summing the 3rd 4th and 5th terms because k goes from 3 to 5

The third term is

-2(3) +5 = -6+5 = -1

The fourth term is

-2(4) + 5 = -8+5 = -3

The fifth term is

-2(5) +5 = -10 +5 = -5

Add these 3 terms together

-1+-3+-5 = -9

14/5 or 2 4/5

Step-by-step explanation:

7 3/5 = 38/5

4 4/5 = 24/5

38/5 - 24/5 = 14/5 = 2 4/5