Odpowiedź:
a) 2(3x+3)- 0,6(x-5)= 19,8
6x+6- 0,6x+ 3= 19,8
5,4x+9= 19,8 |-9
5,4x= 10,8 |:5,4
x= 2
b) (x-12)/4 = (x-2)/9. |*36
9(x-12)= 4(x-2)
9x- 108= 4x-8 |-4x
5x-108= -8 |+108
5x= 100 |:5
x= 20
