Помогите решить х4-5х3+5х2+5х-6=0

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20700
20744
20769
20755

<span><em>402<u>7</u>48</em></span><em>2</em><span>≈ 4030000</span><em>, </em><em>35</em><em>2</em><em><u>9</u>96</em><span>≈3530000</span><em>, </em><em>52</em><em>0</em><em><u>8</u>08</em><span>≈5210000</span><em />

(279-(46+x))-18=125
(279-46-x)-18=125
-x=125-215
-x=-90:(-1)
x=90