4. Решите уравнение: 1 x = -5; 3 г) 8x-13 = 5x - 5; 5) 3x - 1,7 = 2,2; в) 2,2 = 3x - 1,7; д) 16- (2х + 5) = 30; e) 1ly(3y+12) = 4(2y - 3).

Решим уравнения:

1. $$ \frac{1}{3}x = -5 $$ $$ x = -5 \cdot 3 $$ $$ x = -15 $$
2. $$ 3x - 1.7 = 2.2 $$ $$ 3x = 2.2 + 1.7 $$ $$ 3x = 3.9 $$ $$ x = \frac{3.9}{3} $$ $$ x = 1.3 $$
3. $$ 2.2 = 3x - 1.7 $$ $$ 3x = 2.2 + 1.7 $$ $$ 3x = 3.9 $$ $$ x = \frac{3.9}{3} $$ $$ x = 1.3 $$
4. $$ 8x - 13 = 5x - 5 $$ $$ 8x - 5x = -5 + 13 $$ $$ 3x = 8 $$ $$ x = \frac{8}{3} $$ $$ x = 2 \frac{2}{3} $$
5. $$ 16 - (2x + 5) = 30 $$ $$ 16 - 2x - 5 = 30 $$ $$ 11 - 2x = 30 $$ $$ -2x = 30 - 11 $$ $$ -2x = 19 $$ $$ x = -\frac{19}{2} $$ $$ x = -9.5 $$
6. $$ 11y - (3y + 12) = 4(2y - 3) $$ $$ 11y - 3y - 12 = 8y - 12 $$ $$ 8y - 12 = 8y - 12 $$ $$ 8y - 8y = 12 - 12 $$ $$ 0 = 0 $$

   y - любое число

Ответ:

1. x = -15
2. x = 1.3
3. x = 1.3
4. x = 2 \frac{2}{3}
5. x = -9.5
6. y - любое число