Answer:
I'll be referring to this form: ax^2-bx+c
The 4x^2 is the rate that it goes up. If a is greater than 1, then that means the graph gets narrower from the parent function x^2. You can clearly see that in that graph.
The c is always the y-intercept. In this case, you can see that it's 7. The graph clearly shows 7 as it's y-intercept as well, so that matches well.
Sadly, I do not know how to compare the 8x into this situation without a calculator, but that information should be quite enough to see how that function is in that graph.