Using vanilla mathematics:

```
var from:Point = new Point(100, 50);
var to:Point = new Point(80, 95);
var angle:Number = Math.atan2(to.y - from.y, to.x - from.x);
```

Using a new vector representing the difference between the first two:

```
var difference:Point = to.subtract(from);
var angle:Number = Math.atan2(difference.y, difference.x);
```

Note:

`atan2()`

returns radians, not degrees.