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 ==========