Question 1155805
x^3-2x^2-19x+20
(x-5) works
synthetic division

5/1--- -2--- -19---  20
   1----  3---- -4---   0

so the other factor is (x^2+3x-4), and that factors into (x+4)(x-1)

(x-5)(x-1)(x+4)


{{{graph(300,300,-10,10,-10,10,x^3-2x^2-19x+20)}}}