a + b + c + d = 88
a = c : 2 ==> c = 2×a
b = a + 4
d = a+b+c
Metoda grafica:
a /------/
b /------/+4
c /------/------/
d /------/------/------/------/+4
avem 8 segmente egale + 4+4 = 88
88 - (4+4) = 88 - 8 = 80
80 : 8 = 10 (valoarea unui segment egal)
a = 10
b = 10+4 = 14
c = 2×10 = 20
d = 4×10+4 = 44
Verificam:
10 + 14 + 20 + 44 = 88