4（x-2）^2=x^2-44(x^2-4x+4)=x^2-43x^2-16x+20=0(3x-10)(x-2)=0x1=10/3 ,x2=2（3x-1)^2=4（2x-3)^29x^2-6x+1=4(4x^2-12x+9)9x^2-6x+1=16x^2-48x+367x^2-42x+35=0x^2-6x+5=0(x-1)(x-5)=0x1=1 ,x2=5