x(x+2)-(x-1)(x+2)=3 这道题怎么化简

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x(x+2)-(x-1)(x+2)=3 这道题怎么化简
x(x+2)-(x-1)(x+2)=3 这道题怎么化简

x(x+2)-(x-1)(x+2)=3 这道题怎么化简
x(x+2)-(x-1)(x+2)=3
(x²+2x)-(x²+x-2)=3
x²+2x-x²-x+2=3
x+2=3
x=3-2
x=1

x(x+2)-(x-1)(x+2)=3
(x+2)(x-(x-1))=3
(x+2)(x-x+1)=3
x+2=3
x=1

x(x+2)-(x-1)(x+2)=(x+2)(x-x+1)=x+2=3
得x=1

同时提取(x+2)
(x+2)[x-(x-1)]=3
得x+2=3
所以 x=1

x(x+2)-(x-1)(x+2)
=xx+2x-(xx+2x-x-2)
=xx+2x-xx-2x+x+2
=x+2=3
得x=1

X2+2x-x2-2x+x+2=3 (x2表示x的平方,格式调不过来)
X+2=3
X=1