\[0,9x - 7,4 = - 0,4x + 4,3\]
\[0,9x + 0,4x = 4,3 + 7,4\]
\[1,3x = 11,7\]
\[x = 11,7\ :1,3\]
\[x = 117\ :13\]
\[x = 9.\]