Va rog mult la exercitiul 8 ! Dau 100 puncte!

A=6a-10b+18c
3a-5b+9c=7
6a-10b+18c=2*(3a-5b+9c)
6a-10b+18c=7x2=14
A=14
b)
B=4x+16y-28z
x+4y-7z=8
4x+16y-28z=4*(x+4y-7z)
4x+16y-28z=4x8=32
B=32