3. Найдите корень уравнения: a) 13x + 4x = 408 6) 47x-15x = 2144 в) 16у - у + 14 = 299 г) 7b + 6b - 29 = 374

Решение:

• a) $$13x + 4x = 408$$ $$17x = 408$$ $$x = \frac{408}{17}$$ $$x = 24$$
• б) $$47x - 15x = 2144$$ $$32x = 2144$$ $$x = \frac{2144}{32}$$ $$x = 67$$
• в) $$16y - y + 14 = 299$$ $$15y + 14 = 299$$ $$15y = 299 - 14$$ $$15y = 285$$ $$y = \frac{285}{15}$$ $$y = 19$$
• г) $$7b + 6b - 29 = 374$$ $$13b - 29 = 374$$ $$13b = 374 + 29$$ $$13b = 403$$ $$b = \frac{403}{13}$$ $$b = 31$$

Ответ: a) $$x = 24$$, б) $$x = 67$$, в) $$y = 19$$, г) $$b = 31$$