Answer:
[tex]-3x^{2}+13x-4[/tex]
Step-by-step explanation:
You can use the foil technique (first outer inner last)
(3x - 1)(-x + 4) = (3x · (-x)) + (3x · 4) + ((-1) · (-x)) + ((-1) · 4)
= [tex]-3x^{2}+12x+x-4[/tex]
= [tex]-3x^{2}+13x-4[/tex]