Question

Please help me. I am so stuck.
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Answer 1

Converges to -25.

Explanation:

`\sum_(k=1)^(\infty) -5 \cdot ((4)/(5))^(k-1)` converges since
`r=(4)/(5)<1`.

The sum is given by
`(a_1)/(1-r)` where
`a_1` is -5.

`(-5)/(1-(4)/(5))=(-5)/((1)/(5))=-5(5)=-25`.