Yellow Pages or YP as is commonly known, was the original name for the Network Information Service (NIS) created by Sun Microsystems. Nowadays it is mostly called NIS or NIS+.
... is equivalent to
<math>x^2+\frac{b}{a}x=-\frac{c}{a}.</math>
The equation is now in a form in which we can conveniently complete the square[?]. To ...