解方程：-3x²-2x+4=0 x²+2x-99=0 x²-6mx+5m²=0

解方程：-3x²-2x+4=0 x²+2x-99=0 x²-6mx+5m²=0
解方程：-3x²-2x+4=0 x²+2x-99=0 x²-6mx+5m²=0

解方程：-3x²-2x+4=0 x²+2x-99=0 x²-6mx+5m²=0
-3x²-2x+4=0
3x²+2x-4=0
3(x²+2/3x)=4
3(x²+2/3x+1/9)=4+1/3
3(x+1/3)²=13/3
(x+1/3)²=13/9
x+1/3=±√13/3
解得
x=(√13-1)/3或x=-(√13+1)/3
x²+2x-99=0
x²+2x+1=100
(x+1)²=100
x+1=±10
解得
x=9或x=-11
x²-6mx+5m²=0
(x-5m)(x-m)=0
解得
x=5m或x=m

3x²-2x+4=0
3x²+2x-4=0
3(x²+2/3x)=4
3(x²+2/3x+1/9)=4+1/3
3(x+1/3)²=13/3
(x+1/3)²=13/9
x+1/3=±√13/3
解得
x=(√13-1)/3或x=-(√13+1)/3
x²+...

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3x²-2x+4=0
3x²+2x-4=0
3(x²+2/3x)=4
3(x²+2/3x+1/9)=4+1/3
3(x+1/3)²=13/3
(x+1/3)²=13/9
x+1/3=±√13/3
解得
x=(√13-1)/3或x=-(√13+1)/3
x²+2x-99=0
x²+2x+1=100
(x+1)²=100
x+1=±10
解得
x=9或x=-11
x²-6mx+5m²=0
(x-5m)(x-m)=0
解得
x=5m或x=m

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