Răspuns:
a ; b si c sunt i.p. cu 3; 5 si 15
<=> 3a = 5b = 15c
a+b+c = 46 | * 3
=> 3a + 3b + 3c = 138
=> 5b+ 3b + 3c = 138 => 8b+ 3c = 138 | * 5
=> 40b + 15 c = 690
=> 40 b + 5b = 690 => 45 b = 690 | : 45
=> b= [tex]\frac{46}{3}[/tex]
=> 5b = [tex]\frac{230}{3}[/tex]
=> 3a = [tex]\frac{230}{3}[/tex] => a= [tex]\frac{230}{9}[/tex]
=> 15 c = [tex]\frac{230}{3}[/tex] => c= [tex]\frac{230}{3*15}[/tex] = [tex]\frac{46}{9}[/tex]
