已知x²-4x+4+|y+3|=0,求代数式(x-1/2-1)(x-1/2+1)-(x-1/2y-1)²的值

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已知x²-4x+4+|y+3|=0,求代数式(x-1/2-1)(x-1/2+1)-(x-1/2y-1)²的值
已知x²-4x+4+|y+3|=0,求代数式(x-1/2-1)(x-1/2+1)-(x-1/2y-1)²的值

已知x²-4x+4+|y+3|=0,求代数式(x-1/2-1)(x-1/2+1)-(x-1/2y-1)²的值

x²-4x+4等于0,|y+3|等于0,则x为2,y为-3,后面代数式看不懂~~~~“-”是什么意思

x²-4x+4+|y+3|=0
(x-2)²+|y+3|=0
∴x-2=0;y+3=0
即:x=2;y=-3
(x-1/2-1)(x-1/2+1)-(x-1/2y-1)²
=(x-1/2)²-1-(x-y/2-1)²
=(2-1/2)²-1-(2+3/2-1)²
=9/4-1-25/4
=-5