19y-9 is a simpler form of this expression. You can use distributive property to get rigid the brackets (multiply -3 by -4y and 3) , then your expression looks like 12y-9+7y. You then combine like terms to get 19y-9.
4.05400 is hopefully the answer
4800 divide by 3=1600 (2 cars 1 truck)
4600-1600-3000 (6 cars)
3000 divide by 3 = 1000(2cars)
1000 times 2=2000(4 cars )
4800-2000-2800 (2 cars 3 trucks)
$2,800 is your answer