Notam a,b,c cele 3 numere
b = 2×a+3
c = b+8
c-a = 18
a |___|
b |___|___|+3
c |___|___|+3 +8
2 segmente egale +11 - 1 segment egal = 1 segment egal +11 = 18
18 - 11 = 7 (un segment egal)
a = 7
b = 2×7+3 = 14+3 = 17
c = 2×7+11 = 14 + 11 = 25
Verificare:
25 - 7 = 18
a = 7
b = 17
c = 25