Question

a+b+c=170
a-b=50
b-c=30 sa se afle a b c?

Answer 1

      [tex] a+b+c=170\\ a-b=50\\ b-c=30\\ ---------------------\\ Din~prima~relatie~reiese:\\ a-b=50=\ \textgreater \ a=50+b\\ Din~a~doua~relatie~reiese:\\ b-c=30=\ \textgreater \ c=b-30\\ ---------------------\\ inlocuim~si~avem:\\ b+50+b+b-30=170\\ b+50+2b=200\\ b+2b=200-50\\ 3b=150\\ b=150:3\\ b=50\\ ----------------------\\ inlocuim~in~relatia~unu:\\ a-b=50\ \textless \ =\ \textgreater \ a-50=50=\ \textgreater \ a=50+50=\ \textgreater \ a=100\\ inlocuim~in~relatia~doi:\\ b-c=30\ \textless \ =\ \textgreater \ 50-c=30=\ \textgreater \ c=50-30=\ \textgreater \ c=20\\\\ Proba:100+50+20=170\\ 100+70=170\\ 170=170\\\\ [/tex]