5a - 4b = 0; 5a = 4b; a = 4b/5;
Подставляем
(12b/5 - 5b)/(8b/5 - 3b) = (-13b/5)/(-7b/5) = 13/7 = 1 6/7;
5a - 4b = 0; 5a = 4b; a = 4b/5;
Подставляем
(12b/5 - 5b)/(8b/5 - 3b) = (-13b/5)/(-7b/5) = 13/7 = 1 6/7;