\[ 4 \times 14 + 4 \times 4x - 3x = 6x \]
\[ 56 + 16x - 3x = 6x \]
\[ 56 + (16x - 3x) = 6x \]
\[ 56 + 13x = 6x \]
\[ 56 = 6x - 13x \]
\[ 56 = -7x \]
\[ x = \frac{56}{-7} \]
\[ x = -8 \]
Ответ: x = -8