ANSWER
A) -20x²+14x+12; all real numbers
EXPLANATION
The give functions are;
[tex]f(x) = - 4x - 2[/tex]
and
[tex]g(x) = 5x - 6[/tex]
[tex](f \times g)(x) = f(x) \times g(x)[/tex]
[tex](f \times g)(x) = ( - 4x - 2)(5x - 6)[/tex]
[tex](f \times g)(x) = - 20 {x}^{2} + 24x - 10x + 12[/tex]
[tex](f \times g)(x) = - 20 {x}^{2} + 14x + 12[/tex]
This is a polynomial, hence the domain is all real numbers.