I had to get this book for class, and it's horrible. The explanations are sparse...I think the most common explanation (without any explanation previously), is "clearly ___ is the entering variable here". Sometimes, it just says what the next pivot is with. It's clear if you're my professor who contributed to the 3rd edition, but for somebody who's just started learning this, this book is terrible. Also, the notation is weird. Slack variables are denoted with w's, which confused me a lot until I learned that they should be treated as x(n+1) < — subscript — for pivoting rules like Bland's. I got Hillier and Lieberman's Intro to Operation Research book, and its much more concise and clear. Get that instead.