1+8:(1+8:(1-8:(1+4:(1-4:(1-8x)))))=1993
1+8:(1+8:(1-8:(1+4:(1-\frac{4}{1-8x}))))=1993
1+8:(1+8:(1-8:(1+4:(\frac{1-8x-4}{1-8x}))))=1993
1+8:(1+8:(1-8:(1+4:(\frac{-8x-3}{1-8x}))))=1993
1+8:(1+8:(1-8:(1+\frac{4}{\frac{-8x-3}{1-8x}})))=1993
1+8:(1+8:(1-8:(1+\frac{4(1-8x)}{-8x-3})))=1993
1+8:(1+8:(1-8:(1+\frac{4-32x}{-8x-3})))=1993
1+8:(1+8:(1-8:(\frac{-8x-3+4-32x}{-8x-3})))=1993
1+8:(1+8:(1-8:\frac{-40x+1}{-8x-3}))=1993
1+8:(1+8:(1-\frac{8}{\frac{-40x+1}{-8x-3}}))=1993
1+8:(1+8:(1-\frac{8(-8x-3)}{-40x+1}))=1993
1+8:(1+8:(1-\frac{-64x-24)}{-40x+1}))=1993
1+8:(1+8:(\frac{-40x+1+64x+24)}{-40x+1}))=1993
1+8:(1+8:(\frac{24x+25)}{-40x+1}))=1993
1+8:(1+\frac{8}{\frac{24x+25)}{-40x+1}})=1993
1+8:(1+\frac{8(-40x+1)}{24x+25})=1993
1+8:(1+\frac{-320x+8)}{24x+25})=1993
1+8:(\frac{24x+25-320x+8)}{24x+25})=1993
1+8:(\frac{-296x+33)}{24x+25})=1993
1+\frac{8}{\frac{-296x+33)}{24x+25}}=1993
1+\frac{8(24x+25)}{-296x+33}=1993
1+\frac{192x+200}{-296x+33}=1993
\frac{-296x+33+192x+200}{-296x+33}=1993
\frac{-104x+233}{-296x+33}=1993
-104x+233=1993(-296x+33)
-104x+233=-589928x+65769
-104x+589928x=65769-233
589824x=65536
x=\frac{65536}{589824}=\frac{1}{9}