a)3x^2+2x-1=0 b)x^2-3x+2=0 c)4x^2-12x+5=0 d)x^2-5x+6=0 e)2x^2-6x+1=0 f)2x^2+5x+0 g)x^2+x-2=0 h)x^2-4x+3=0 i)2x^2+5x-3=0 j)x^2+6x-16=0
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