6道初三用因式分解法解二元一次方程题 老大们帮帮忙
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/08/31 01:00:26
6道初三用因式分解法解二元一次方程题 老大们帮帮忙
①169(x+3)²-196(x-2)²=0
②4x²-5x-7=0
③4(x+3)²=9(2x-1)²
④3(3-x)²+x(x-3)=0
⑤(x+2)²+3(x+2)-4=0
⑥(3x-2)(x-4)+11=0
①169(x+3)²-196(x-2)²=0
②4x²-5x-7=0
③4(x+3)²=9(2x-1)²
④3(3-x)²+x(x-3)=0
⑤(x+2)²+3(x+2)-4=0
⑥(3x-2)(x-4)+11=0
①169(x+3)²-196(x-2)²=0
[13(x+3)]²-[14(x-2)]²=0
[(13x+39)+(14x-28)][(13x+39)-(14x-28)]=0
(27x+11)(-x+67)=0
x1=-11/27
x2=67
②4x²-3x-7=0
(4x-7)(x+1)=0
x1=7/4
x2=-1
③4(x+3)²=9(2x-1)²
[2(x+3)]²-[3(2x-1)]²=0
[(2x+6)+(6x-3)][(2x+6)-(6x-3)]=0
(8x+3)(-4x+9)=0
x1=-3/8
x2=9/4
④3(3-x)²+x(x-3)=0
3(x-3)²+x(x-3)=0
(x-3)[3(x-3)+x]=0
(x-3)[3x-9+x]=0
(x-3)[4x-9]=0
x1=3
x2=9/4
⑤(x+2)²+3(x+2)-4=0
[(x+2)+4][(x+2)-1]=0
(x+6)(x+1)=0
x1=-6
x2=-1
⑥(3x+2)(x-4)+11=0
3x^2+2x-12x-8+11=0
3x^2-10x+3=0
(3x-1)(x-3)=0
x1=1/3
x2=3
[13(x+3)]²-[14(x-2)]²=0
[(13x+39)+(14x-28)][(13x+39)-(14x-28)]=0
(27x+11)(-x+67)=0
x1=-11/27
x2=67
②4x²-3x-7=0
(4x-7)(x+1)=0
x1=7/4
x2=-1
③4(x+3)²=9(2x-1)²
[2(x+3)]²-[3(2x-1)]²=0
[(2x+6)+(6x-3)][(2x+6)-(6x-3)]=0
(8x+3)(-4x+9)=0
x1=-3/8
x2=9/4
④3(3-x)²+x(x-3)=0
3(x-3)²+x(x-3)=0
(x-3)[3(x-3)+x]=0
(x-3)[3x-9+x]=0
(x-3)[4x-9]=0
x1=3
x2=9/4
⑤(x+2)²+3(x+2)-4=0
[(x+2)+4][(x+2)-1]=0
(x+6)(x+1)=0
x1=-6
x2=-1
⑥(3x+2)(x-4)+11=0
3x^2+2x-12x-8+11=0
3x^2-10x+3=0
(3x-1)(x-3)=0
x1=1/3
x2=3