Răspunsuri

2014-10-09T15:08:46+03:00
a+3xb+3xc=a+3(b+c)=14+3x25=14+75=89

5xa+2xc+2xb=5xa+2(b+c)=5x14+2x25=70+50=120

axb+axc+5xa-16xb-16xc=a(b+c)+5xa-16(b+c)=14x25+5x14-16x25=350+70-400=420-400=20
Mulțumesc frumos.Primele doua le-am facut si eu, dar nu eram sigura.La ultima insa ma incurcasem.