(2x+2y)m+(3x-3y)n+y-5x
=2mx+2my+3nx-3ny+y-5x
=(2m+3n-5)x+(2m-3n+1)y
只要x和y系数为0就符合题意
2m+3n-5=0
2m-3n+1=0
相加
4m-4=0
所以m=1
n=(5-2m)/3=1