[tex] \sqrt{(5 - 4x) ^{2} } = 9 \\ \\ |5 - 4x| = 9 \\ \\ 5 - 4x = 9 \\ \\ - 4x = 9 - 5 = 4 \\ \\ = > x = 1 \\ \\ 5 - 4x = - 9 \\ \\ - 4x = - 9 - 5 = - 14 \\ \\ = > x = \frac{7}{2} \\ \\ = > x_{1} = 1 \\ \\ \: \: \: \: \: \: \: x_{2} = \frac{7}{2} [/tex]
