Решите уравнение только 7

Решите задачу:

$4x {}^{ - 2} + 4x {}^{ - 1} + 1 = 0 \\ 4 \times \frac{1}{x {}^{2} } + 4 \times \frac{1}{x} + 1 = 0 \\ \frac{4}{x {}^{2} } + \frac{4}{x} + 1 = 0 \\ ( \frac{2}{x} + 1) {}^{2} = 0 \\ ( \frac{2 + x}{x} ) {}^{2} = 0 \\ \frac{2 + x}{x} = 0 \\ 2 + x = 0 \\ x = - 2 \\ \\ 9x {}^{ - 2} - 12x {}^{ - 1} + 4 = 0 \\ 9 \times \frac{1}{x {}^{2} } - 12 \times \frac{1}{x} + 4 = 0 \\ \frac{9}{x {}^{2} } - \frac{12}{x} + 4 = 0 \\ ( \frac{3}{x} - 2) {}^{2} = 0 \\ ( \frac{3 - 2x}{x} ) {}^{2} = 0 \\ \frac{3 - 2x}{x} = 0 \\ 3 - 2x = 0 \\ - 2x = - 3 \\ x = \frac{3}{2} \\ x = 1 \frac{1}{2}$