Find the zero of the polynomial x4-34x+225=?

x^4 - 34x + 225 = 0 Add spaces to improve readability. We use Shift-6 for powers. Now study this page until it seems obvious:
https://en.wikipedia.org/wiki/Polynomial_remainder_theorem

This is not an easy problem.
http://www.wolframalpha.com/input/?i=solve+x^4+-+34x+%2B+225+%3D+0+

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