Răspunsuri

2014-11-19T16:59:32+02:00
A)5x(2x-1)=152x-1=15:5
2x-1=3
2x=3+1
2x=4
x=4:2
x=2

b)3x(4x+5)=39

12x+15=39
12x=39-15
12x=34
x=34/12
x=2

c) 6x(3x+9)=-72

3x+9=-72:6
3x+9=-12
3x=-12-9
3x=-21
x=-21:3
x=-7
2014-11-19T17:00:58+02:00
A) 10x-5=15  10x=10 x=1
b)12x+15=39 12x=24 x=2
c)18x+54=-72  18x=-18 x=-1