we have
f(x)=6x+2
g(x)=-5x-9
Find out the product
so
f(x)*g(x)=(6x+2)*(-5x-9)
Applying distributive property
f(x)*g(x)=(6x)*(-5x)+(6x)*(-9)+(2)*(-5x)+(2)*(-9)
f(x)*g(x)=-30x^2-54x-10x-18
combine like terms
f(x)*g(x)=-30x^2-64x-18
the answer is the option D