👤

Daca a+b= 21 si b+c= 30 , sa se calculeze:
a+2*b+c
c-a


Răspuns :

a=30-21=9
b=21-9=12
c=30-12=18

a+2×b+c=30+21=51
9+24+18=51

c-a=18-9=9
a+2b+c=30+21=52...................