Н0З = 6х(х-3)
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27/х = 20/(х - 3) + 1/6
27 * 6(х-3) = 20 * 6х + х*(х-3)
162(х- 3) = 120х + x^2 - 3x
162x - 486 = 120x + x^2 - 3x
-x^2 - 120x + 162x + 3x = 486
-x^2 + 45x - 486 = 0
x^2 - 45x + 486 = 0
D = 2025 - 4*486 = 2025 - 1944 = 81 √D = 9
x1 = (45 + 9)/2 = 27
x2 = (45 - 9)/2 = 18
Ответ: х1 = 27
х2 = 18