Ответ:
1. В
2. Б
3. Б
4.
1) Б
2) Г
3) В
4) Д
5.(без проверок)
1) x + 3 = 5x + 11
x - 5x = 11 - 3
-4x = 7
x = -4/7 (запиши как дробь)
2) 9 - 3x = 5x + 25
3x - 5x = 25 - 9
-2x = 16
-x = 8
x = -8
3) -5.4 - 1.5x = 0.3x - 3.6
-5.4 + 3.6 = 0.3x + 1.5x
- 1.8 = 1.8x
x = -1
4) 2(5x + 2) - (2x - 3) = 15
(10x + 4) - (2x - 3) = 15
(10x + 4) - (2x - 3) = 15
10x + 4 - 2x + 3 = 15
8x + 7 = 15
8x = 15 - 7
8x = 8
x = 1
5)
