The region R in the xy plane is bounded by the graph of y x 2 the x axis and the lines 0 and x 4 If the density of R is 1 the mass of R is given by the integral 5 0 The moment about the y axis of R is given by the integral m My x y da The moment about the z axis of R is given by the integral M 0 Evaluating these integrals the center of mass of R is located at dx dx