1)
14x-75=-30-x
14x + x = 75 - 30
15x = 45
x = 45 : 15
x = 3
2)
(x+0,2) / 5 = x/10
5 * x = 10 * ( x + 0,2)
5x = 10x + 2
10x - 5x = -2
5x = -2
x = -2 : 5
x = -0,4