Find maxima and minima?

First you have to find the derivative.i'm assuming this is calculus. the derivative of this is 33x^2 -10x. then you can equal this to 0. 33x^2-10x=0 you can factor the left x(33x-10) so x =0 ,10/33. make a number line with 0 and 10/33 as your points and plug a number to the left of 0,inbetween 0 and 10/33,and to the right of 10/33. you know for sure when you do this if it changes from + to - it's a max if from - to + its a min