For the equation (2x - 2) (4x +4) i got 8x² -8 can you explain why this is correct or incorrect?

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

P= price tax is 4% added to the price. which expression shows the total price including tax?

Anut store normally sells cashews for? $4.00 per pound and peanuts for? $1.50 per pound. but at the end of the month the peanuts had not sold? well, so, in order to sell 40 pounds of? peanuts, the manager decided to mix the 40 pounds of peanuts with some cashews and sell the mixture for $2.00 per pound. how many pounds of cashews should be mixed with the peanuts to ensure no change in the? profit?