Untitled

<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<title>Teste</title>
	<script language="javascript">
		function soma(x,y){
			var a = parseInt(x);
			var b = parseInt(y);
			document.write((a+b));
		}

	</script>
</head>
<body>
	<input type="number" size="5" name="txt1" id="t1">
	<input type="number" size="5" name="txt2" id="t2">
	<input type="button" name="bt1" value="SOMA" onclick="soma(t1.value,t2.value);">
</body>
</html>