Is it possible to use the broadband (landline/wired) internet connection through tablets? If yes, how?

[L]

You can also use the connection via USB ports, if your router supports a USB connection. But most routers only have one USB connection so you'd only be able to hook one tablet up like that.

Just an aside, are you having trouble with your wifi connection on the tablet? If you're having trouble with the tablets losing their wifi connection, is it just after you turn the tablet on? I've noticed that our tablet does that about half the time but ONLY just after turning on and the solution is as simple as going into the settings on the tablet, turning off wifi and turning it on again and then everything is back to normal. However, I'll be interested to see how it goes now because our wireless network was showing up twice on the tablet in the list of available networks and I found out yesterday how to remove the bogus one and so far, so good. I think when we tried to set up a wifi connection, we made a mistake and the tablet couldn't connect, then we got it right, but ended up with our network showing up twice in the network list and possibly the tablet has been trying to connect to the connection we messed up. Have you perhaps done something similar? If so, find the list of networks on your tablet, when your tablet is connected and using the internet reliably. In the list, you'll see one network that you're connected to and that one you leave there. (This SHOULD be your own network, not your neighbour's unsecured network!) Remove all the other networks that your tablet shouldn't be using. This is probably done by pressing and holding on a network and waiting for a menu to pop up and one option should be to remove the network from the list.

If your wifi is set up and working properly, there shouldn't really be any advantage in using wired.