Answer:
First One:
x { 6, 9, 12, 15, 18 }
y { -14, -4, 8, 22, 38 }
Explanation:
Not sure if the other guy is trolling...
The x values constantly rise by 3, so we find the y value change
The differences are 10, 12, 14, 16
If we do it again we get 2, 2, 2. So since we did the reduction 2 times, this is a quadratic function.
Why isn't "the third one"
Constant rise by 2
Change of 9, 9, 9, 9
This is one reduction, so it is not quadratic.