Let ABCD be a cyclic quadrilateral with circumcircle \omega and let AC and BD intersect at X. Let the line through A parallel to BD intersect line CD at E and \omega at Y \neq A. If AB = 10, AD = 24, XA = 17, and XB = 21, then the area of \triangle DEY can be written in simplest form as \frac{m}{n}. Find m + n.