Respuesta :

pegah
the slope intercept form is like : y = mx +b that m is slope and b is y-intercept 
so you can say : 9y = 3x - 27 ⇒ 9/9y = 3/9x -27/9 ⇒ y = 1/3x -3 :))
i hope this be helpful 
have a nice day 
♥ Slope intercept form:
y = mx +b 
Slope intercept form of
-3x+9y=-27

y = 1/3x -3