<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>calculadora</title>
</head>
<body>
<form id="form1" name="form1" method="post" action="">
<table width="218" border="1">
<tr>
<th width="97" scope="row">numero_1</th>
<td width="105"><p>
<label for="cmdNum1"></label>
<input type="text" name="cmdNum1" id="cmdNum1" />
</p></td>
</tr>
<tr>
<th scope="row">numero_2</th>
<td><label for="cmdNum2"></label>
<input type="text" name="cmdNum2" id="cmdNum2" /></td>
</tr>
<tr>
<th scope="row"> </th>
<td><input name="cmdSuma" type="submit" id="cmdSuma" value="sumar" />
<input name="-resta" type="submit" id="cmdResta2" value="-" /><input name="cmdResta" type="submit" id="cmdResta" value="-" />
<input name="cmddivide" type="submit" id="cmdDivide" value="-" /></td>
</tr>
</table>
<?
$cmdNum1=$_post["cmdNum1"];
$cmdNum2=$_post["cmdNum2"];
$sumar=$_post["cmdSuma"];
$suma= $cmdNum1+$cmdNum2;
echo "la suma es : =$suma" ;
?>
</form>
</body>
</html>