Răspunsuri

2014-11-18T18:12:43+02:00
1)a=120*b/100 =>a=6b/5=> 5a=6b
2)a=b-4/5=>a=(5b-4)/5 => 5a=5b-4
egalezi 1) si 2) 6b=5b-4
b=-4
a=120*(-4)/100
a=-4,8