Question 865755
x1		y1	x2	y2				
-1      		9      	4      	6    				
								
slope m =		(y2-y1)/(x2-x1)						
(	6    	-	9    	)/(	4    	-	-1    	)
(	-3    	/	5    	)  				
m=		-  1/ 2