解方程:,(100-x-y)-(x+y)=2

问题描述:

解方程:,(100-x-y)-(x+y)=2

(100-x-y)-(x+y)=2
100-x-y-x-y =2
100-2x-2y =2
-2(x+y)=98
-(x+y) =49
即-x-y =49