Răspuns :
a+b+c=30
a=3cx2,a=2b
a=6c=2b,c=a/6=2b/6
2b+b+2b/6=30
12b+6b+2b=180
20b=180
b=9
a=18
c=3
a=3cx2,a=2b
a=6c=2b,c=a/6=2b/6
2b+b+2b/6=30
12b+6b+2b=180
20b=180
b=9
a=18
c=3
a+b+c=30
a=2x3c
a=2b
c=a:6=2b:6
2b+b+2b:6=30
2b+b+2b=30x6
12b+6b+2b=180
20b=180
b=9
a=2x9=18
c=18:6=3
a=2x3c
a=2b
c=a:6=2b:6
2b+b+2b:6=30
2b+b+2b=30x6
12b+6b+2b=180
20b=180
b=9
a=2x9=18
c=18:6=3