Can i have with this, i have drawn out a graph and marked my points so far.

D. 2x²

Step-by-step explanation:

Ok, so the first thing to do is remember the first number in parentheses is x, and the second number is y.

You're trying to figure out which expression turns x into y in each set.

Just by plugging in the numbers into each expression I found that the answer is 2x².

I'll prove this starting with (1, 2).

1² = 1  

2 x 1 = 2

So, y = 2x²!

Next, (2, 8).

2² = 4

2 x 4 = 8

So, y = 2x²!

I'm not going to demonstrate with the other two but I hope you understand. Just plug the values of x and y into the equation and see which is correct.