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(3+x)^2-25=07+23x-20x^2=03-x^2=-2x19x+10=10x+x^25x-18=2(x-50)3x-11-(x-3)^2=0

题目详情
(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
▼优质解答
答案和解析
(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