Răspuns :
a-b=140
a=(bx2)+72
b |----|
a |----|----|+72
140-72=68 (b)
68x2+72=136+72=208 (a)
Verificare: 208-68=140
a=(bx2)+72
b |----|
a |----|----|+72
140-72=68 (b)
68x2+72=136+72=208 (a)
Verificare: 208-68=140