(2x+3Y-5)平方+|x-3y-4|=0
2x+3y-5=0
x-3y-4=0
解得:x=3,y=-1/3
x^ny^n+2
=(xy)^n+2
=(3*(-1/3))^n+2
=(-1)^n+2
=-1+2,(n为奇数)
=1.