bjr
2x + 1 = -4
2x = -4 - 1
x = -5/2
x = -2,5
7 + 5x = 4
5x = 4 - 7
x = -3/5
4x - 3 = -7
4x = -7 + 3
x = -4/4 = - 1
-5 + 3x = 1
3x = 1 + 5
x = 6/3 = 2
-7x + 6 = 5
-7x = 5 - 6
x = 1/7
8 - 9x = -2
-9x = -2 -8
x = 10/9
ex 2
2/3 * 3/2x = 5 * 3/2
x = 15/2 = 7,5
5/7x * 7/5 = -8 * 7/5
x = -56/5
-3/4 * (-4/3) = -8 * (-4/3)
x = 32/3
-5/7x * (-7/5) = 3 * (-7/5)
x = -21/5
