答案是
9(1). x^2-10x-4=0
x^2-10x=4
x^2-10x+25=4+25
(x-5)^2=29
x-5=±√29
x=5±√29
(2).x^2+5x-3=0
x^2+5x=3
x^2+5x+25/4=3+25/4
(x+5/2)^2=37/4
x+5/2=±(√37)/2
x=(-5±√37)/2
(3).x^2+4x/3-3=0
x^2+4x/3+4/9=3+4/9
(x+2/3)^2=31/9
x+2/3=±√(31/9)
x=(-2±√31)/3
(4).x^2-4x=-1
x^2-4x+4=-1+4
(x-2)^2=3
x-2=±√3
x=2±√3
不可能你都不会啊