Question

решите уравнение и сделайте проверку 1/x-1/7x=2/7

Answer 1

$frac{1}{x} - frac{1}{7x} = frac{2}{7} / *7x$

7 - 1 = 2x

-2x = -6 

x = 3 

проверка: 

$frac{1}{3} - frac{1}{7*3} = frac{2}{7}$

$frac{1}{3} - frac{1}{21} = frac{2}{7}$

$frac{7}{21} - frac{1}{21} = frac{2}{7}$

$frac{6}{21} = frac{2}{7}$

$frac{6}{21} = frac{6}{21}$