Răspuns:
Explicație pas cu pas:
a)
x = 2y/11
z = 7y/11
x + y + z = 80
2y/11 + y + 7y/11 = 80
2y/11 + 11y/11 + 7y/11 = 80
20y/11 = 80
y = 11*80/20 = 44
x = 2*44/11 = 8
z = 7*44/11 = 28
_________________
b) x = 5y/3
z = 7y/3
x + 2y - z = 192
5y/3 + 2y - 7y/3 = 192
5y/3 + 6y/3 - 7y/3 = 192
4y/3 = 192
y = 3*192/4 = 144
x = 5*144/3 = 240
z = 7*144/3 = 336