3x-2y=5 (1) kx+(k-1)y=7 (2) (2)*5-(1) 5kx+(5k-5)y-3x+2y=35-5 (5k-3)x+(5k-3)y=30 x+y=1 所以(5k-3)x+(5k-3)y=5k-3 所以5k-3=30 k=33/5 ========== 如果答案对你有所帮助,
