Plz help this is khan and I don’t remember how to do this

What is the 12th term of b(n)=-4-2(n-1)

Solutions for 2x+7 less than or equal to 3x-5

Boris needs to buy plastic spoons. brand a has a box 42 spoons for $2.37. brand b has a box of 72 spoons for $3.57. find the unit price for each brand. then state which brand is the better buy based on the unit price. round your answer to the nearest cent.