3-6a 2b=0 1-3a 2b=-13-6a+2b=0 1-3a+2b=-13x^2-2x-1=0

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3-6a 2b=0 1-3a 2b=-13-6a+2b=0 1-3a+2b=-13x^2-2x-1=0

3-6a 2b=0 1-3a 2b=-13-6a+2b=0 1-3a+2b=-13x^2-2x-1=0
3-6a 2b=0 1-3a 2b=-1
3-6a+2b=0
1-3a+2b=-1
3x^2-2x-1=0

3-6a 2b=0 1-3a 2b=-13-6a+2b=0 1-3a+2b=-13x^2-2x-1=0
第一题:
3-6a+2b=0
1-3a+2b=-1
等式两边分别相减 => (3-6a+2b)-(1-3a+2b)=0-(-1)
=> 2-3a=1
=> a=1/3
将a的值带入第二个等式 => 1-3*(1/3)+2b=-1
=> 2b=-1
=> b=-(1/2)
第二题:
因式分解 => (3x+1)(x-1)=0
=> 3x+1=0 或x-1=0
=> x=-(1/3) 或 x=1

{a+1/2b=c,1/2a-b-c=1,3a+b=-2 求解abc