Răspunsuri

2014-04-24T10:55:04+03:00
M-27=f  m=f+27
m-27-7=4(f-7)  si inlocuim
f+27-27-7=4f-28
f-7=4f-28
f-4f=-28+7
-3f=-21
3f=21
f=7           m=7+27=34