2x纺 7x-7=0配方法

（1）提公因式：x(x-1)=0,所以x1=0,x2=1；（2）十字相乘：(x+7)(x-3)=0,所以x1=-7,x2=3；（3）2(x^2+4x+4-4)-7=0,2(x+2)^2-15=0,(x

1）-3X的平方+22X-24=0即:x^2-22/3x+8=0(x-11/3)^2=49/9x-11/3=(+/-)7/3x1=11/3+7/3=6x2=11/3-7/3=4/32）2x^2+6=7

4X^2-7X-36=04(x-7/8)^2-49/16-36=04(x-7/8)^2=625/16x-7/8=±25/8x=4,x=-9/46X^2-7X-5=06(x-7/12)^2-49/24-

4X^2-7X-36=0(2x-7/4)²=36+49/16(2x-7/4)²=625/16x=8,x=-18/46X^2-7X-5=0X^2-(7/6)X-(5/6)=0(x-7

3x²-7x+2=0；3(x-7/6)²=25/12;(x-7/6)²=25/36;x-7/6=±5/6;x=2或1/3;

2x平方-7x+6=0(x-2)(2x-3)0x1=2x2=1.5

3x²-2x-7=03x²-2x=7x²-2/3x=7/3x²-2/3x+1/9=7/3+1/9(x-1/3)²=22/9x-1/3=±√22／3x1

2x－7x－6=0这是一元一次方程解是：x=-1.2再问：能否写出详细过程，谢谢再答：这是一元一次方程2x－7x－6=0-5x-6=0-5x=6x=6÷（-5）x=-1.2

2x^2-7x=6x^2-7x/2=3x^2-7x/2+49/16=3+49/16(x-7/4)^2=97/16x-7/4=±根号97/4x=(7-根号97)/4,x=(7+根号97)/4

2x^2-7X-4=02（x^2-7/2x)-4=02[x^2-2*(7/4)x+(7/4)^2]-2*(7/4)^2-4=02(x-7/4)^2-49/8-4=02(x-7/4)^2=81/8(x-

2x²-7x+6=0x²-7x/2=-3（x-7/4）²=-3+49/16（x-7/4）²=1/16解得x1=2,X2=3/2纯手动,累呀

直接配方有：第一题,2x^2-7x+3=2(x-7/4)^2+3-49/8=0所以,2(x-7/4)^2=25/8,(x-7/4)^2=25/16所以,开方得到：x-7/4=±5/4,x=3或1/2第

（2x+1）（x-4）=0求的x=-1/2或x=4再问：我还是不够聪明、哈哈想错了，我想了(x+1)(2x+4)

(3X+7)(X-1)=0.3(X^2+4/3X+(2/3)^2)=7+3*(2/3)^2(X-2/3)^2=7/3+4/9=25/9=(5/3)^2X+2/3=5/3X+2/3=-5/3X1=1;X

2x^2-7x=-3x^2-7/2x=3/2x^2-7/2x+(7/4)^2=3/2+(7/4)^2(x+7/4)^2=73/16

2x²-7x=10x²-7x/2=5x²-7x/2+(7/4)²=5+49/16(x-7/4)²=129/16x-7/4=±(√129)/4x1=(7

x^2-11x/3=-7/3x^2-11x/3+121/36=-7/3+121/36(x-11/6)^2=37/36x-11/6=±√37/6x=(11-√37)/6,x=(11+√37)/6

3[(x-2/3)^2-31/9]=0(x-2/3)^2=31/9x-2/3=+-根号（31/9）x=2/3+-根号（31/9）

1.x^2-x=7/4x^2-x+1/4=2x-1/2=根号2x=根号2+1/22.x^2+2x-4/3=0x^2+2x=4/3x^2+2x+1=7/3x=1/3根号21-1