1)... 2x-3=0,5+x ... 2x-x = 3+0,5 ... x=3,5
3)... 1/3-21/4=3x-1/5 ... 3x = 1/3-21/4-1/5 |×60
180x = 20 - 315 - 12
x = 307/180 = 1,70(5)
4)... (9-2x)*3=3(x-1/4) | :3
9-2x = x - 1/4 | *4
36-2x = 4x - 1
36+1 = 4x+2x
6x = 37
x = 37/6=6,1(6)
2)... 7intregi si 1/2=7,5 ; 3 intregi si 2/5=3,4
=> (7,5-3,4)=-2x-x
deci: -x=4,1 de unde x= -4,1