Question

Determinati (a,b,c) dp (3,7,8) ,daca c+12=a+b

Answer 1

a/3=b/7=c/8 => a=3k ,b=7k, c=8k
c+12=a+b => 8k+12=10k => 12=2k => k=6 
daca k=6 => a=18 , b=42, c=48

Answer 2

{a, b, c} d.p. {3, 7, 8}
=> a=3k
=> b=7k
=> c=8k
c+12=a+b
8k+12=3k+7k
8k+12=10k
8k-10k=-12
-2k=-12 /•(-1)
2k=12
k=6
a=3•6=18
b=7•6=42
c=8•6=48