The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0\\[1 em]x_2 &= 11.899\\[1 em]x_3 &= 2.101 \end{aligned} $$Step 1:
Factor out $ \color{blue}{ -x }$ from $ -x^3+14x^2-25x $ and solve two separate equations:
$$ \begin{aligned} -x^3+14x^2-25x & = 0\\[1 em] \color{blue}{ -x }\cdot ( x^2-14x+25 ) & = 0 \\[1 em] \color{blue}{ -x = 0} ~~ \text{or} ~~ x^2-14x+25 & = 0 \end{aligned} $$One solution is $ \color{blue}{ x = 0 } $. Use second equation to find the remaining roots.
Step 2:
The solutions of $ x^2-14x+25 = 0 $ are: $ x = 7-2 \sqrt{ 6 } ~ \text{and} ~ x = 7+2 \sqrt{ 6 }$.
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