Código PHP:
<html>
<head><title></title></head>
<body>
<h1>Detalle de Empresa</h1>
<?php
$RfcEmp=$_POST['RfcEmp'];
$consul_empre="select empresas where RfcEmp=$RfcEmp";
$consult=mysql_query($consul_empre);
echo "<table border='1'>";
$fila_emp=mysql_fetch_array($consult);
print "'<tr>' . '<td>' . 'rfc' . '</td>' . '<td>' . '<input type=\'text\' name=\'rfc\' id=\'rfc\' value=\"<?php echo $fila_emp['RfcEmp']; ?>\" />' . '</td>' . '</tr>'";
echo "<tr><td>Nombre</td><td><input type=\"text\" name=\"nombre\" id="nombre" value="<?php echo $fila_emp[$NombreEmp]; ?>" /> </td></tr>";
?>
<body>
<html>