求解下列一元二次方程第一题：（4x+3）（5-x）=02t：(x-1)^2+2x(x-1)3t: 2x^2-4x-5=04t: -3x^2-4x+4=05t: 3x(x-1)=2-2x6t: (x-1)(x+2)=707t: x(x+6)=78t: (3-x)^2+x^2=9

求解下列一元二次方程第一题：（4x+3）（5-x）=02t：(x-1)^2+2x(x-1)3t: 2x^2-4x-5=04t: -3x^2-4x+4=05t: 3x(x-1)=2-2x6t: (x-1)(x+2)=707t: x(x+6)=78t: (3-x)^2+x^2=9
求解下列一元二次方程
第一题：（4x+3）（5-x）=0
2t：(x-1)^2+2x(x-1)
3t: 2x^2-4x-5=0
4t: -3x^2-4x+4=0
5t: 3x(x-1)=2-2x
6t: (x-1)(x+2)=70
7t: x(x+6)=7
8t: (3-x)^2+x^2=9

求解下列一元二次方程第一题：（4x+3）（5-x）=02t：(x-1)^2+2x(x-1)3t: 2x^2-4x-5=04t: -3x^2-4x+4=05t: 3x(x-1)=2-2x6t: (x-1)(x+2)=707t: x(x+6)=78t: (3-x)^2+x^2=9
第一题：（4x+3）（5-x）=0
(4x+3)(x-5)=0
(x+3/4)(x-5)=0
x=-3/4,x=5
2t：(x-1)^2+2x(x-1)
是不是漏了=0
(x-1)(x-1+2x)=0
(x-1)(3x-1)=0
x=1,x=1/3
3t:2x^2-4x-5=0
x^2-2x=5/2
x^2-2x+1=5/2+1
(x-1)^2=7/2=[±√(7/2)]^2=(±√14/2)^2
x-1=±√14/2
x=(2+√14)/2,x=(2-√14)/2
4t:-3x^2-4x+4=0
3x^2+4x-4=0
3x^2-2x+6x-4=0
x(3x-2)+2(3x-2)=0
(3x-2)(x+2)=0
x=2/3,x=-2
5t:3x(x-1)=2-2x
3x(x-1)+2x-2=0
3x(x-1)+2(x-1)=0
(x-1)(3x+2)=0
x=1,x=-2/3
6t:(x-1)(x+2)=70
x^2+x-2-70=0
x^2+x-72=0
x^2+9x-8x-72=0
x(x+9)-8(x+9)=0
(x+9)(x-8)=0
x=-9,x=8
7t:x(x+6)=7
x^2+6x-7=0
x^2-x+7x-7=0
x(x-1)+7(x-1)=0
(x-1)(x+7)=0
x=1,x=-7
8t:(3-x)^2+x^2=9
x^2-6x+9+x^2=9
2x^2-6x=0
2x(x-3)=0
x=0,x=3

额。。哥们，这也太简单了吧，是基础题诶`
1. 4x+3=0 或 5-x=0
x=-3/4 或 x=5
看不请呢
基本都这形式，把右边都放左边去，使右边等于0就好做了~
自己看初三的书，上面写的清清白白。
因式分解法 直接开方法等等

：（4x+3）（5-x）=0
x1=-3/4 , x2=5
2t：(x-1)^2+2x(x-1) =0
(x-1)(x-1+2x)=0
(x-1)(3x-1)=0
x1=1 , x2=1/3
3t: 2x^2-4x-5=0
2(x^2-2x)=5
2(x-1)^2=5+2=7
(x-1)^2=3.5

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：（4x+3）（5-x）=0
x1=-3/4 , x2=5
2t：(x-1)^2+2x(x-1) =0
(x-1)(x-1+2x)=0
(x-1)(3x-1)=0
x1=1 , x2=1/3
3t: 2x^2-4x-5=0
2(x^2-2x)=5
2(x-1)^2=5+2=7
(x-1)^2=3.5
x-1=±√3.5
x1=1+√3.5 ,x2=1-√3.5
4t: -3x^2-4x+4=0
3x^2+4x-4=0
(3x-2)(x+2)=0
x1=2/3 ,x=-2
5t: 3x(x-1)=2-2x
3x(x-1)=2(1-x)
3x(x-1)+2(x-1)=0
(x-1)(3x+2)=0
x1=1 ,x=-2/3
6t: (x-1)(x+2)=70
x^2+x-2=70
x^2+x-72=0
(x-8)(x+9)=0
x1=8 ,x2=-9
7t: x(x+6)=7
x^2+6x=7
x^2+6x-7=0
(x-1)(x+7)=0
x1=1 ,x2=-7
8t: (3-x)^2+x^2=9
9-6x+x^2+x^2=9
2x^2-6x=0
2x(x-3)=0
x1=0 ,x2=3

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