Can someone explain this question to me?

Question

What intervals should I use to test whether or not the graph is concave up or down. I know that no points or equations are given so we have to estimate.

Here is the URL for the graph.

imgur dotcom/FdQCV

Answer 1

Looks like there are inflection points at x = -3/2 and x=2

So, i"d answer that

f is concave down in (-oo,-3/2) and (2,oo)
f is concave up in (-3/2,2)