Question

daca a,b si c sunt nr naturale, astfel incat a+b=55 si b+c=45 sa se calculeze 2×a+4×b+2×c

Answer 1

a+b=55
b+c=45     a+b+b+c=55+45=100=a+2b+c
2a+4b+2c=2(a+2b+c)=2*100=200

Answer 2

a+b=55
b+c=45(+)

a+2b+c=55+45
a+2b+c=100

2a+4b+2c=
=2(a+2b+c)=
=2*100=200