Let's perform the synthetic division
color(white)(aaaa)aaaa33color(white)(aaaaa)aaaaa|∣color(white)(aaaa)aaaa99color(white)(aaaaaa)aaaaaa-19−19color(white)(aaaaaa)aaaaaa-28−28color(white)(aaaa)aaaa1212
color(white)(aaaaaaaaaaaa)aaaaaaaaaaaa_________
color(white)(aaaa)aaaacolor(white)(aaaaaaa)aaaaaaa|∣color(white)(aaaa)aaaacolor(white)(aaaaaaaa)aaaaaaaa2727color(white)(aaaaaaa)aaaaaaa2424color(white)(aaa)aaa-12−12
color(white)(aaaaaaaaaaaa)aaaaaaaaaaaa________
color(white)(aaaa)aaaacolor(white)(aaaaaaa)aaaaaaa|∣color(white)(aaaa)aaaa99color(white)(aaaaaaaa)aaaaaaaa88color(white)(aaaaaa)aaaaaa-4−4color(white)(aaaaaa)aaaaaacolor(red)(0)0
(9x^3-19x^2-28x+12)/(x-3)=(9x^2+8x-4)9x3−19x2−28x+12x−3=(9x2+8x−4)
The remainder is =0=0 and the quotient is =9x^2+8x-4=9x2+8x−4