Răspuns :
ab-ac=135
ab-ac = a(b-c) = 135 dar a =9 :
9 (b-c) = 135
b-c = 135 / 9
b-c = 15
ab-ac = a(b-c) = 135 dar a =9 :
9 (b-c) = 135
b-c = 135 / 9
b-c = 15
[tex]ab-ac=135 \\ a=9 \\ b-c=? \\ ab-ac=135 \\ a(b-c)=135 \\ 9(b-c)=135 \\ b-c=135:9 \\ \boxed{b-c=15}[/tex]