Question

Which of the following functions matches the graph (the graph is in the comment section)? Please explain why each of the others is not the correct function.

A. 4x^3
B. x^2(4x + 5)
C. x(4x^2 + 5x - 25)
D. 4x^2 + 5x^2 - 25x + 25

Thanks in advance to ALL answers!

Answer 1

Here is the graph.

Answer 2

Have you tried some sample points? 0 is always a good one to try, as the arithmetic is usually quite simple. what do you get for each of A-D if you set x=0? It looks like you can immediately eliminate 1 answer choice right there. Then try x = 1 on the rest....

Answer 3

After x = 1, I'd try x = -1, because there's an interesting bump in the curve at x = -1.