Question

afla numerele a si b,stiind ca 3a+3b=600 si a-b=140

Answer 1

3a+3b=600
adica a+b=600:3
a+b=200
a=200-b
a-b=140
200-b-b=140
200-(2xb)=140
(2xb)=200-140
2xb=60
b=30
a=200-b
a=200-30
a=170
a=170, b=30