#laptop case

There is a huge crack on the back of my parents Sony Vaio Fit laptop, on the bottom right. Every time I touch it or try to fix it, there is a big pop noise that makes me very nervous. When I try to close it slightly, wires and the inside of the laptop show, and I think if I close it any further...

So I've had my Acer Aspire 7 for a couple months now and I ended up denting it somehow, I'm not really sure how. (If anyone has another solution please let me know). But I thought the most efficient way would be by getting a case (Like a case that stays on and covers the back), but I've been...