Explicație pas cu pas:
a+b=43
(b+1)-4=a× 3/5
[(b+1)-4]×5 =a
3
[(b+1)-4]×5 +b=43
(b-3)×5+3b=129
5b-15+3b=129
8b-15=129
8b=129+15
8b=144
b=144/8
b=18
a=43-b=43-18
a=25
