Which function has the widest graph?
a. y=2x^2 b. y=x^2 c. y=0.5x^2 d. y=-x^2
do you have to graph each one to find the answer?

You don't have to graph each of the answers, because you can just visualize the thing in your head.
B and D are the same, just facing different directions.
A is very narrow, since you multiply x by 2.
This means that the widest graph is C. y = 0.5x^2, because you divide x by 2.