Răspuns :
a+b+c+d=80
c=3×a => 3×a = a+b => 3×a-a = b => 2×a = b
c=a+b => c = a+2×a=> c=3×a
d=a+c => d= a+3×a => d= 4×a
a+b+c+d= a+2×a+3×a+4×a=80 => 10×a=80 =>a =8
b= 8×2=16
c=8×3=24
d=8×4=32
a+b+c+d=80
c=3×a => 3×a = a+b => 3×a-a = b => 2×a = b
c=a+b => c = a+2×a=> c=3×a
d=a+c => d= a+3×a => d= 4×a
a+b+c+d= a+2×a+3×a+4×a=80 => 10×a=80 =>a =8
b= 8×2=16
c=8×3=24
d=8×4=32