A square is drawn on 1st quadrant of XY plane having consecutive coordinates (counter - clockwise, starting from left bottom) as P(2,3), Q(7,3), R(7,8), S(2,8) respectively. Thereafter, each side of the square is doubled considering P as a fixed point and the new square becomes PQ'R'S'. Now this new square is mirrored with respect to X axis. What will be the coordinates for the image of R'?