[рони]

vas88811,

var arr3 = [5, 8, 6, 9];
 var arr4 = [1, 3, 7, 5];
 var arr5 = [];
 for (var x=0;x<arr4.length;x++){
    arr5[x] = arr4[x] //сохраняем структуру arr4 в arr5
 }
 arr4.sort(function(a,b){return b - a});
 var arr6 = [];
 for (var n=0;n<arr5.length;n++){
 for (var x=0;x<arr4.length;x++){
 if (arr4[n]==arr5[x]) {
 arr6.push(arr3[x]);
 } }}
 alert(arr4+'\n'+arr6)