what interval should I have?? it only says y = 0........ it only gives me one interval to evaluate it.... whats the second one???
It also doesn't say anything about "area"! If there was some other part of the problem, asking you to find the area between the graphs, then you are not given any "interval" but you are given two graphs: $\displaystyle y= -x^2+ 3x$ and $\displaystyle y= 0$. That second is a horizontal line. Graph them. It should be easy to see what region is referred to.