a)
[tex]\frac{1}{4}x = \frac{1}{6} \ \ /\cdot24\\\\6x = 4 \ \ /:6\\\\\boxed{x=\frac{2}{3}}[/tex]
b)
[tex]3 - 8\cdot9x = 3\\\\-72x = 3-3\\\\-72x = 0\\\\\boxed{x = 0}[/tex]
c)
[tex]\frac{1}{3}=5x \ \ /\cdot3\\\\15x = 1 \ \ /:15\\\\\boxed{x = \frac{1}{15}}[/tex]
d)
[tex]\frac{61}{8}\cdot(-9) = \frac{1}{3}x\\\\-\frac{549}{8} = \frac{1}{3}x \ \ /\cdot24\\\\8x = 3\cdot(-549})\\\\8x = -1647 \ \ /:8\\\\\boxed{x = -205\frac{7}{8}}[/tex]
