The slope-intercept form:
[tex]y=mx+b[/tex]
m - the slope
b - the y-intercept
[tex]3x-9y=27 \ \ \ |-3x \\
-9y=-3x+27 \ \ \ |\div (-9) \\
\boxed{y=\frac{1}{3}x-3} \\ \\
\\ \hbox{the slope - } \boxed{m=\frac{1}{3}} \\
\hbox{the y-intercept - } \boxed{b=-3}[/tex]