如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少

问题描述:

如果x+y=2z,且x≠y,那么x/x-z+y/y-z等于多少

=2
因为x+y=2z
所以【x-z=z-y】
所以原式=x/(z-y)-y/(z-y)
=(x-y)/(z-y)
=(x-y)/(x-z)
=(x-z+z-y)/(x-z)
=1+(z-y)/(x-z)
=1+(z-y)/(z-y)
=1+1
=2为什么x-z=z-y呢因为x+y=2z所以x=2z-y =z+z-y所以x-z=z-y