The slope of the line is determined by the slope-intercept form of the 
equation. That is solving for y. or y = mx + b, where m = slope and 
b = y-intercept.

The equation 3x + 2y = 6 is written in standard form so we need to 
rewrite it in slope - intercept form.

3x + 2y = 6                
3x + 2y - 3x = - 3x + 6    --> subtract 3x both sides so to separate 2y
     2y = -3x + 6          --> divide both sides by 2 so y will be left
      y = -3x + 6
           2    2
      y = -3x + 3
           2 
  m = -3/2, this is the slope
  b = 3, this is the y-intercept