Question

9上 知道的 1,x（x-14）=o 2,x平方+12x+27=0 3,x平方=x+56

Answer 1

1. x(x-14)=0 x=0或x=14 2. x+12x+27=0 (x+3)(x+9)=0 x=-3或x=-9 3. x=x+56 x-x-56=0 (x-8)(x+7)=0 x=8或x=-7 4. 4x-45=31x 4x-31x-45=0 (x-9)(4x+5)=0 x=9或x=-5/4 5. x(5x+4)=5x+4 (x-1)(5x+4)=0 x=1或x=-4/5 6. -3x+22x-24=0 3x-22x+24=0 (3x-4)(x-6)=0 x=4/3或x=6 7 (x+8)(x+1)=-12 x+9x+8+12=0 x+9x+20=0 (x+4)(x+5)=0 x=-4或x=-5 8 (3x+2)(x+3)=x+14 3x+11x+6=x+14 3x+10x-8=0 (3x-2)(x+4)=0 x=2/3或x=-4