( x - 2 )( x - 8 )( x + 5 ) =
( x^2 - 10x + 16 )( x + 5 ) =
x^3 - 10x^2 + 16x + 5x^2 - 50x + 80 =
x^3 + ( - 10 + 5 )x^2 + ( 16 - 50)x + 80 =
x^3 - 5x^2 - 34x + 80
