Why is my screen glitching?

My sero 8's screen is glitching and when i press the power button the lock screen shows for about a half a second then it disappears and has lines every where. Then when i exit out again and turn it back on, it does the same thing. I have found anything helpful yet and i really need this tablet to work. i can still touch the screen and hear everything so it's not frozen. I did factory reset it but that did not work either.