Răspuns :
a+b+c=72
a+b=52
c=72-52=20
b=c+15
b=20+15
b=35
a+b=52
a+35=52
a=52-35
a=17
V:20+35+17=72 ( A )
35+17=52 ( A )
35-20=15 ( A )
a+b=52
c=72-52=20
b=c+15
b=20+15
b=35
a+b=52
a+35=52
a=52-35
a=17
V:20+35+17=72 ( A )
35+17=52 ( A )
35-20=15 ( A )