如何解x+y>11,10x+y-18=10y+x
问题描述:
如何解x+y>11,10x+y-18=10y+x
答
∵x+y>11
10x+y-18=10y+x
=>x-y=2
即x=y+2
∴y+2>11-y
y>9/2
x>13/2