Răspuns:
Explicație pas cu pas:
a) a+b=64
a/b=7/9 a=7b/9 7b/9+b=64 7b+9b=9×64 16b=9×64 b=36
a=64-36=28
b) b-a=18
a/b=2/5 b - 2b/5=18 5b-2b=5×18 3b=5×18=⇒b=5×6=30
a=b-18=30-18=12
c)b-a=5
a/ b=3/7×14/8=3/4 b-3b/4=5 4b-3b=5x4 b=20
a=20-5=15
d) a/b=1/19 a/1=b/19=(a+b)/(1+19)=30/20=3/2
a=3/2
b=3x19/2=57/2
