7x + 5 = 5x + 7
7x - 5x = 7 - 5
2x = 2
x = 1
4x = 4 + 2(3x + 5)
4x = 4 + 6x + 10
4x - 6x = 14
-2x = 14
x = -7
4(2x - 5) - x = 3x + 8
8x - 20 - x = 3x + 8
7x - 3x = 8 + 20
4x = 28
x = 7
7(3x - 2) - 6(4x + 7) = 18x
21x - 14 - 24x - 42 = 18x
-3x - 56 = 18x
-21x = 56
x = -\(\frac{56}{21}\) = -\(\frac{8}{3}\) = -2 \(\frac{2}{3}\)
2(6x - 5) - 5(3x + 4) = 7x - 10
12x - 10 - 15x - 20 = 7x - 10
-3x - 30 = 7x - 10
-10x = 20
x = -2
9(2x - 1) + 2 = 2(8x - 3) + 2x
18x - 9 + 2 = 16x - 6 + 2x
18x - 7 = 18x - 6
-7 = -6
Решений нет