几道关于初中解X的数学题

来源:百度知道 编辑:UC知道 时间:2024/05/07 20:14:38
(3+x)^2-25=0
7+23x-20x^2=0
3-x^2=-2x
19x+10=10x+x^2
5x-18=2(x-50)
3x-11-(x-3)^2=0
要有步骤!有些有两个答案的要标出来!好的+分!

(3+x)^2-25=0
(3+x+5)(3+x-5)=0
(x+8)(x-2)=0
x1=-8,x2=2

7+23x-20x^2=0
20x^2-23x-7=0
(5x-7)(4x+1)=0
x1=7/5,x2=-1/4

3-x^2=-2x
x^2-2x-3=0
(x-3)(x+1)=0
x1=3,x2=-1

19x+10=10x+x^2
x^2-9x-10=0
(x-10)(x+1)=0
x1=10,x2=-1

5x-18=2(x-50)
5x-18=2x-100
3x=-82
x=-82/3

3x-11-(x-3)^2=0
3x-11-x^2+6x-9=0
x^2-9x+20=0
(x-4)(x-5)=0
x1=4,x2=5

(3+x)^2-25=0
(3+x)^2=25
3+x=5或3+x=-5
x=2或x=-8

7+23x-20x^2=0
20x^2-23x-7=0
(5x-7)(4x+1)=0
x=7/5或x-1/4

3-x^2=-2x
x^2-2x-3=0
(x-3)(x+1)=0
x=3或x=-1

19x+10=10x+x^2
x^2-9x-10=0
(x-10)(x+1)=0
x=10或x=-1

5x-18=2(x-50)
5x-18=2x-100
3x=-82
x=-82/3

3x-11-(x-3)^2=0
3x-11-(x^2-6x+9)=0
x^2-9x+20=0
(x-5)(x-4)=0
x=5或x=4

3+x)^2-25=0
(3+x)^2=25
3+x=5或3+x=-5
x=2或x=-