Question 467075
x+y+z=	0			--------------				1
2x+y-z=	30			--------------				2
3x-4y+2z=-49		--------------				3
																
consider equation 1 &2				Eliminate y												
Multiply 1 by	-1								Multiply 2 by 1									
we get																
-x-y-z=	0						
2x+y-z=	30						
Add the two 																
x-2z=	30	-------------				4	
consider equation 2 & 3	Eliminate y		
Multiply 2 by -4											
Multiply 3 by 	1												
we get 																
-8x-4y+4z=-120							
3x-4y+2z=-49							
Add the two 																
-5x-8y+6z=-169	-------------5				5		
Consider (4) & (5)			Eliminate x													
Multiply 4 by				5												
Multiply (5) by				1												
we get																
5x-10z=	150										
-5x+6z=-169										
Add the two 																
-4z=-19										
/-4															
z=4.75	OR	4  3/ 4												
																
Plug the value of z in						5										
-5x+28.5=-169										
-5x=-197.5													
x=39.5	OR 39  1/ 2												
plug value of x & z in					1											
39.5	+y+4.75	=	0									
y=-39.5-4.75+0									
	y=	-44.25	OR	-44 1/4