Răspuns :
a+b=25
b+c=18
a)a+2b+c
a=25-b; c=18-b
25-b+2b+18-b=25+18=43
b)25a+41b+16c=25*(25-b) + 41b + 16*(18-b)=625-25b+41b+288-16b=625+288
=913
a+b=25
b+c=18
a)a+2b+c
a=25-b; c=18-b
25-b+2b+18-b=25+18=43
b)25a+41b+16c=25*(25-b) + 41b + 16*(18-b)=625-25b+41b+288-16b=625+288
=913