First, find the index of
the element you want to remove:
var array = [2, 5, 9];
var index = array.indexOf(5);
Then remove it with splice:
if (index > -1) {
array.splice(index, 1);
}
The second parameter of splice is
the number of elements to remove. Note, splice modifies
the array in place and returns a new array containing the elements that have been removed.