200/x - 200/x+10 = 1

200/x-200/(x+10) = 1 /x(x+10) ,  x≠0,x≠-10
200(x+10)-200x=x(x+10)
200x+2000-200x=x²+10x
2000=x²+10x
x²+10x-2000=0
D=100+8000=8100,√D=√(8100)=90
x1=(-10+90)/2=80/2=40
x2=(-10-90)/2=-100/2=-50
x1=40,x2=-50
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