Question

(3a-5b)/(2a-3b), если 5a-4b=0 Как решить?

Answer 1

5a - 4b = 0;  5a = 4b;  a = 4b/5;

Подставляем

(12b/5 - 5b)/(8b/5 - 3b) = (-13b/5)/(-7b/5) = 13/7 = 1 6/7;