Question 666499
m=		- 4/5						 						
Plug value of  the slope  and point(7,	12	) in							
Y	=	m	x	+	b									
12	=	- 4/5	*	7	+	b								
12	=	-5 3/5	+	b										
b=	12    	+	28/5											
b=	88/ 5													
So the equation  will be														
Y 	=	- 4/5	x	+	88/5
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3      	x		-4	y  	=	8								
Find the slope of this line														
														
-4	y  	=	-3      	x	+	8    								
Divide by	-4													
	y  	=	  3/ 4	x	+	-2    								
Compare this equation with y=mx+b,					m= slope & b= y intercept									
slope m =	 3/4													
														
The slope of a line perpendicular to the above line will be the negative reciprocal										-4/3				
Because m1*m2 =-1														
The slope of the required line will be	-4/3					
								
m=	-4/3	,point	(	-1	,	1	)							
Find b by plugging the values of m & the point in														
y=mx+b														
1	=	4/ 3	+	b										
b=	- 1/3													
m=	-1 1/3													
The required equation is y=	-4/ 3	x	-  1/ 3	


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PARALLEL								
								
								
3    	x		-4	y  	=	8		
Find the slope of this line								
make y the subject								
-4	y  	=	-3    	x	+	8		
Divide by	-4							
	y  	=	 3/4	x		-2    		
Compare this equation with y=mx+b								
slope m =	 3/4							
The slope of a line parallel to the above line will be the same								
The slope of the required line will be			 3/4					
m=	 3/4	,point	(	-1	,	1	)	
Find b by plugging the values of m & the point in								
y=mx+b								
1	=	-  3/ 4	+	b				
b=	1.75							
m=	 3/4							
Plug value of  the slope  and b		in y = mx +b			
The required equation is y  	=	 3/4	x	+	7/ 4	
								
								
						
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