1. Найди корни уравнений

Решение уравнений: **1. Найди корни уравнений** а) $2x + 5 = 3x - 1 \Rightarrow 5 + 1 = 3x - 2x \Rightarrow x = 6$ б) $4(x - 3) = 20 \Rightarrow x - 3 = 5 \Rightarrow x = 8$ в) $3(2x + 1) - 2(x - 4) = 7 \Rightarrow 6x + 3 - 2x + 8 = 7 \Rightarrow 4x + 11 = 7 \Rightarrow 4x = -4 \Rightarrow x = -1$ г) $(2x + 6)(x - 4) = 0 \Rightarrow x_1 = -3, \ x_2 = 4$ д) $3x^2 - 12x = 0 \Rightarrow 3x(x - 4) = 0 \Rightarrow x_1 = 0, \ x_2 = 4$ е) $\frac{x}{3} - \frac{x}{5} = 2 \Rightarrow \frac{5x - 3x}{15} = 2 \Rightarrow \frac{2x}{15} = 2 \Rightarrow 2x = 30 \Rightarrow x = 15$ ж) $x^2 - 49 = 0 \Rightarrow x^2 = 49 \Rightarrow x = \pm 7$ з) $x^2 - 5x + 6 = 0 \Rightarrow (x-2)(x-3) = 0 \Rightarrow x_1 = 2, \ x_2 = 3$ **2. Найди корни уравнений** а) $5x - 4 = 2x + 8 \Rightarrow 5x - 2x = 8 + 4 \Rightarrow 3x = 12 \Rightarrow x = 4$ б) $-3(2x + 1) = 9 \Rightarrow 2x + 1 = -3 \Rightarrow 2x = -4 \Rightarrow x = -2$ в) $2(3x - 1) + 4(2 - x) = 10 \Rightarrow 6x - 2 + 8 - 4x = 10 \Rightarrow 2x + 6 = 10 \Rightarrow 2x = 4 \Rightarrow x = 2$ г) $(3x - 9)(x + 7) = 0 \Rightarrow 3(x - 3)(x + 7) = 0 \Rightarrow x_1 = 3, \ x_2 = -7$ д) $4x^2 + 20x = 0 \Rightarrow 4x(x + 5) = 0 \Rightarrow x_1 = 0, \ x_2 = -5$ е) $\frac{x}{4} + \frac{x}{6} = 5 \Rightarrow \frac{3x + 2x}{12} = 5 \Rightarrow \frac{5x}{12} = 5 \Rightarrow 5x = 60 \Rightarrow x = 12$ ж) $x^2 - 100 = 0 \Rightarrow x^2 = 100 \Rightarrow x = \pm 10$ з) $x^2 - 8x + 15 = 0 \Rightarrow (x-3)(x-5) = 0 \Rightarrow x_1 = 3, \ x_2 = 5$