Dr. Benton just got his PhD, and he wants to print copies of his thesis in hardcover book format. He could use Middletown Printing, paying a setup fee of $39 and $3 for every book printed. Alternately, he could go through Oxford University, paying an up-front fee of $35 and $5 per book. It turns out that, given the number of books Dr. Benton wants to print, the two options cost the same amount. How many books is that? What is the amount?​