-3x + 5y = 2x + 3y
 + 3x + 3x
-------------------------------
 5y = -x + 3y
 -3y - 3y
---------------------------
 2y = - x
 ----- ------- 
 2 2
y = -1/2x
The slope of this line is -1/2. Slope intercept form is y = mx + b, where m stands for slope and b stands for y - intercept.