Suppose the decimal 0.28 is equal to {1}{n}+{2}{n^2}, where n is negative. Find n.
1(n) + 2(n^2) = 0.28
2n^2 + n - 0.28 = 0 [ multiply through by 100 ]
200n^2 + 100n - 28 = 0
50n^2 + 25n - 7 = 0
(5n - 1)(10n + 7) = 0
Only the second factor will produce a negative n
10n + 7 = 0
10n = -7
n = -7/10
