# Link to equation and change text?

I am interested in linking to an equation - but being able to change the text.

I had thought I could combine this answer and this answer, but I cannot seem to get it to work.

I have attempted a variety of syntaxes similar to

\hyperref[eq:name]{my text describing the equation here}


but I cannot seem to get it to work.

This is the code I am currently using (well my equation is considerably more complicated but I have the same problem here)

\begin{align*}
y = x\label{testp}
\end{align*}
\hyperref[testp]{generalized form}


I get the following warning

LaTeX Warning: Hyper reference testp' on page 4 undefined on input line 108.

-

For this it is easiest to use a \hypertarget and \hyperlink combination since you technically don't have a "counter that you can reference" - this is provided by \refstepcounter, which marks a position that you can hyperlink to:

\documentclass{article}
\usepackage{amsmath,hyperref}% http://ctan.org/pkg/{amsmath,hyperref}
% Taken from http://tex.stackexchange.com/a/17138/5764
\makeatletter

Since \hypertarget sets its target at the baseline, it has to be raised for any practical application. See \hypertarget` seems to aim a line too low.