The roots of polynomial $ p(t) $ are:
$$ \begin{aligned}t_1 &= \frac{\sqrt{ 30 }}{ 3 }\\[1 em]t_2 &= - \frac{\sqrt{ 30 }}{ 3 } \end{aligned} $$The solutions of $ -3t^2+10 = 0 $ are: $ t = - \dfrac{\sqrt{ 30 }}{ 3 } ~ \text{and} ~ t = \dfrac{\sqrt{ 30 }}{ 3 }$.
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