Răspuns :
a=7-b
7 x (7-b) +3b=29
49-7b+3b=29
49-4b=29
-4b=29-49
-4b=-20 /X-1
4b=20
b=20 :4=5
a=7-5=2
7 x (7-b) +3b=29
49-7b+3b=29
49-4b=29
-4b=29-49
-4b=-20 /X-1
4b=20
b=20 :4=5
a=7-5=2