Btn Sliding Up

programming flash
1

var i:Number = 1;

btn_1_.addEventListener(MouseEvent.MOUSE_OVER, fadein)

function fadein(evtObj:MouseEvent):void{
//var btn_move_in:Tween = new Tween(btn_1, “y”, Regular.easeOut, xposition, xposition - btn_1.height, 1.25, true);
var btn_fade_in:Tween = new Tween(btn_1, “alpha”, Regular.easeOut, 0, 1, 2, true)
var i:Number = 1
btn_1_.scaleY = +=i;
}

why doesn’t that work? i want the btn_1_ to kind of slide up.