Respuesta :

Answer:

a = 12+6(n-1) (BOTTOM LEFT)

Step-by-step explanation:

a = x + y(n-1)

x = the original amount; y = amount it increases by

a = 12+6(n-1)

Answer:

12 + (n-1)*6

Step-by-step explanation:

The first book costs 12 dollars

The next book and each additional book costs 6 dollars

Let n the the number of books

The first book is 12,  so we multiply by 1 less book for the 6 dollar books,

or n-1

The cost for all the books is 12 + (n-1)*6