Cannot get this checkbox to build?

http://ift.tt/2mMuj0V

I tried to fix other errors so it may look tad different but this is the best i could do.

override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning()
    Box49.setImage(#imageLiteral(resourceName: "UnCheckBox"), for: .normal)
    Box49.setImage(#imageLiteral(resourceName: "CheckBox"), for: .selected)

    Box50.setImage(#imageLiteral(resourceName: "UnCheckBox"), for: .normal)
    Box50.setImage(#imageLiteral(resourceName: "CheckBox"), for: .selected)

    Box51.setImage(#imageLiteral(resourceName: "UnCheckBox"), for: .normal)
    Box51.setImage(#imageLiteral(resourceName: "CheckBox"), for: .selected)

}

@IBAction func Box49(_ sender: UIButton) {
    sender.isSelected = !(sender as AnyObject).isSelected
}


@IBAction func Box50(_ sender: UIButton) {
    sender.isSelected = !(sender as AnyObject).isSelected
}


@IBAction func Box51(_ sender: UIButton) {
    sender.isSelected = !(sender as AnyObject).isSelected
    }