Please help me. I am so stuck.
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Answer:
Converges to -25.
Step-by-step explanation:
[tex]\sum_{k=1}^{\infty} -5 \cdot (\frac{4}{5})^{k-1}[/tex] converges since [tex]r=\frac{4}{5}<1[/tex].
The sum is given by [tex]\frac{a_1}{1-r}[/tex] where [tex]a_1[/tex] is -5.
[tex]\frac{-5}{1-\frac{4}{5}}=\frac{-5}{\frac{1}{5}}=-5(5)=-25[/tex].