(x-3)(x-1)=8解：x²-4x+3=8x²-4x+3-8=0x²-4x-5=0(x-5)(x+1)=0x-5=0,x+1=0x1=5,x2=-1
x²-4x+3＝8x²-4x-5＝0（x-5）（x+1）＝0x＝5或-1
