ket qua la y D Y c -1/52 Y c x=m-8/m+3 Y d 13/3 y c x=can 5 -1 hoac x= -can5 -1 Y b a khac +- 1 a khac -2, akhac 0 Y c 3 Ket qua =1 Ket qua la 25/2