Calcul m2 java

$('form[name="frmbmi"]').submit(function(){
  var This = $(this);
  if(This.valid()) {
   var taille= This.find('input[name="taille"]').val();


   var point = This.find('input[name="point"]').val();

   var imc = ( parseFloat(taille) / Math.sqrt(lbs) );

   This.find('input[name="txtbmi"]').val(parseFloat(imc).toFixed(1));
  }
  return false;
 });