Screen is broken. Image is distorted and patchy.

(My phone is actually a Samsung Galaxy J3, but they didn't have an option for that.)

Okay so, I misplaced my phone yesterday, and when I found it, it was broken. Everything seemed fine, but when I turned it on, the display was patchy and a section of the touch screen wouldn't work. I tilted the device a little to reveal a couple of otherwise-invisible cracks in the screen.

I live in a house of six people, so anything could have happened to it, but I think someone must have knocked it off of a table or something.

Anybody know how to fix it? Will I have to replace the whole thing?

My mom suggested a factory reset. Would that do anything?