Let X and Y correspond to the horizontal and vertical coordinates in the triangle with corners at

Question:

Let X and Y correspond to the horizontal and vertical coordinates in the triangle with corners at (2,0), (0,2), and the origin. Let fX,Y (x,y) = 15/28(xy2 + y) for (x, y) inside the triangle, and fX,Y (x,y) = 0 otherwise.
a. Find the covariance of X and Y.
b. Find the correlation of X and Y.