Question

Найдите 61а-11b+50 если 2а-7b+5/7a-2b+5=9

Answer 1

$frac{2a - 7b + 5}{7a - 2b + 5} = 9 Rightarrow \ 2a - 7b + 5 = 63a - 18b + 45 Rightarrow \ 61a - 11 b + 40 = 0 Rightarrow \ 61a - 11 b + 50 = 10$