The roots of polynomial $ p(t) $ are:
$$ \begin{aligned}t_1 &= 15 \sqrt{ 14 }i\\[1 em]t_2 &= -15 \sqrt{ 14 }i \end{aligned} $$Step 1:
Combine like terms:
$$ t^2 \color{blue}{-2200} + \color{blue}{5350} = t^2+ \color{blue}{3150} $$Step 2:
The solutions of $ t^2+3150 = 0 $ are: $ t = 15 \sqrt{ 14 } i ~ \text{and} ~ t = -15 \sqrt{ 14 } i $.
You can use step-by-step quadratic equation solver to see a detailed explanation on how to solve this quadratic equation.