What the simplify form for –3(x + 3) + 4x

If f(x) = 3-2x and g(x) =1/x+5 to what is the value (f/g)(8)

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax

F(x) = 1/x g(x)=x-4 can you evaluate (g*f)(0) ? why or why not?