a=b
a-15<b+15 de 2 ori....=>a-15+b+15=15*2*3
-------------------------
a=?b=?
a+b=?
a-15=b+15-15.....=> b=15*3 a) |___|___|___|=>a=15*3
b=45 si a =45 b) |___|___|___|=>b=15*3
45-15<45+15 de 2 ori ---------------------------------------
30<60 de 2 ori ....(60:2=30) 6*15=90 creioane in total
45+45=90 de creioane
45-15+45+15=
=30+60
=90 creioane in total