10) Решите уравнение 2,1x-4,2=1,4x

\( 2.1x - 4.2 = 1.4x \)

\( 2.1x - 1.4x = 4.2 \)

\( 0.7x = 4.2 \)

\( x = \frac{4.2}{0.7} \)

\( x = 6 \)

Ответ: 6