化简方程式 4(x-y)-(x-y)²-4=0

化简方程式 4(x-y)-(x-y)²-4=0
化简方程式 4(x-y)-(x-y)²-4=0

化简方程式 4(x-y)-(x-y)²-4=0
4(x-y)-(x-y)²-4=0两边同时乘以-1
(x-y)²-4(x-y)+4=0
（x-y-2）²=0

4(x-y)-(x-y)²-4=-（(x-y)²+4-4(x-y)）=-(x-y-2)²=0
所以，x-y-2=0

4(x-y)-(x-y)²-4=0
(x-y-2)²=0
x-y-2=0