Răspunsuri

2014-06-16T17:28:32+03:00
A+b=34.5
a-b=8.9 => a=8.9+b

8.9+b+b=34.5
2b=34.5-8.9
2b=25.6
b=25.6:2
b=12.8

a=8.9+12.8
a=21.7