4. Решите уравнение и сделайте проверку: г) 7y²+y=0;

7y² + y = 0
y(7y + 1) = 0
y = 0 или 7y + 1 = 0
y = 0 или 7y = -1
y = 0 или y = -\(\frac{1}{7}\)

Проверка:
1) y = 0: 7 * 0² + 0 = 0 + 0 = 0
2) y = -\(\frac{1}{7}\): 7 * \(- \frac{1}{7}\)² - \(\frac{1}{7}\) = 7 * \(\frac{1}{49}\) - \(\frac{1}{7}\) = \(\frac{1}{7}\) - \(\frac{1}{7}\) = 0
Ответ: y₁ = 0, y₂ = -\(\frac{1}{7}\)