1. Square both sides
2. Subtract x from both sides
3. Divide by 1999
4. Square both sides
5. Simplify lefthand side
6. Subtract x
7. Common denominator and combine fractions
8. Divide by 1999
9. Square both sides
10. FOIL it out
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um, not going to finish, I just realized that this is annoying, and I am probably going to make a math error at some point, throwing the whole thing off. So I decided to look at the problem from a "is there an obvious answer" approach instead of a "how would I solve this" approach, and yes, the obvious answer is zero.