👤
a fost răspuns

Daca a+b=21 si b+c=30, sa se calculeze: a+2×b+c. B)c-a. C) 2×a+3×b+c. D) a+4×b+3×c

Răspuns :

a+b=21
b+c=30
a)
a+2*b+c=
a+b+b+c=
a+2b+c=21+30=51
c)
2*a+3*b+c=a+b+a+b+b+c=
2a+3b+c=
21+21+30=72
d)
a+4*b+3*c
a+b+b+c+b+c+b+c=
a+4b+3c=
21+30+30+30=111
c)
(b+c)-(a+b)=
(b+c)-a-b=
30-21=9