Javascript Starter

<hmtl>

<head>

<script>
function func()
{
var xv = document.getelementbyid("xv").value;
var yv = document.getelementbyid("yv").value;
var yz = document.getelementbyid("yz").value;
var xz = document.getelementbyid("xz").value;
var yc = document.getelementbyid("yc").value;
var xc = document.getelementbyid("xc").value;
var yv = (((xv - xz) / (xc - xz)) * (yc - yz)) + yz;
alert(yv);
}

</script>

</head>

<body>


<form>
<h>Valor 1:</h><p>
<input id="xv" type="Valor 1" /><p>
<h>x0:</h><p>
<input id="xc" type="x0" /><p>
<h>x100:</h><p>
<input id="xz" type="x100" /><p>
<h>y0:</h><p>
<input id="yc" type="y0"  /><p>
<h>y100:</h><p>
<input id="yz" type="y100"  /><p>

<input type=button value='Calcular' onClick='func();'><p>

</form>


</body>
</html>