The roots of polynomial $ p(s) $ are:
$$ \begin{aligned}s_1 &= -\frac{ 49 }{ 20 }+\frac{\sqrt{ 1159 }}{ 20 }i\\[1 em]s_2 &= -\frac{ 49 }{ 20 }- \frac{\sqrt{ 1159 }}{ 20 }i \end{aligned} $$Step 1:
Get rid of fractions by multipling equation by $ \color{blue}{ 10 } $.
$$ \begin{aligned} s^2+\frac{49}{10}s+\frac{89}{10} & = 0 ~~~ / \cdot \color{blue}{ 10 } \\[1 em] 10s^2+49s+89 & = 0 \end{aligned} $$Step 2:
The solutions of $ 10s^2+49s+89 = 0 $ are: $ s = -\dfrac{ 49 }{ 20 }+\dfrac{\sqrt{ 1159 }}{ 20 }i ~ \text{and} ~ s = -\dfrac{ 49 }{ 20 }-\dfrac{\sqrt{ 1159 }}{ 20 }i$.
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