How do I do this? I asked my teacher and I just don't get it.

I can just say you how to do the first one, others you can do it by yourself.

x = -4

Given y = 2x+1

Therefore, y = 2(-4)+1 = -8+1 = -7

So, x = -4, y = -7

You just need to put the value of x and do the sum. You can do it by yourself. It's easy

i believe it's a.

i'm not sure on this one, most likely correct.