[tex]e) \: 9x - 7 = 3x + 5 \\ 6x = 12 \\ x = 2 \\ f) \: 3 - 10 - x = 9 - 4 \times 3 \\ - 7 - x = 9 - 12 \\ - 7 + 3 = x \\ x = - 4 \\ g) \: 5 - 2x = 9 - 6x \\ 4x = 4 \\ x = 1 \\ h) - 6 + 4x = \frac{5}{x} + 4 \\ 4x - \frac{5}{x} = 10 \\ 4 {x}^{2} - 5 = 10x \\ 4 {x}^{2} - 10x - 5 = 0 \\ Δ = 100 - 4 \times 4 \times ( - 5) = 100 + 80 = 180 \\ \sqrt{Δ} = \sqrt{180} = \sqrt{36 \times 5} = 6 \sqrt{5} \\ x_{1} = \frac{ 10 - 6 \sqrt{5} }{8} = \frac{2(5 - 3 \sqrt{5)} }{8} = \frac{5 - 3 \sqrt{5} }{4} \\ x_{2} = \frac{5 + 3 \sqrt{5} }{4} [/tex]
