Resposta :
a/b = 2 --> a = 2b
a+b<20 --> 2b+b < 20 --> 3b < 20 --> b < 20/3 --> b = 6
a = 2b --> a = 2.6 --> a = 12
a.b = 12.6 = 72 (a)
a+b<20 --> 2b+b < 20 --> 3b < 20 --> b < 20/3 --> b = 6
a = 2b --> a = 2.6 --> a = 12
a.b = 12.6 = 72 (a)