<PRE><B>Question 144967</B>
x-2y+3=-4--------------1
3x+y-z=0--------------2
2x+3y-5z=1------------3

From 2, z=3x+y
So 3 becomes, 2x+3y-5(3x+y)=1
Solving the above we get, -13x-2y=1---------4
From 1 we have, x-2y=-7

Solving 1 and 4 we have
-13x-2y=1-----------4
x-2y=-7-------------5

Multiply 13 on both sides of 5, we have now 13x-26y=-91

Subtracting one from the other, we have
13x-26y=-91
-13x-2y=1
-------------
0-28y=-90
-----------
y=90/28=45/14
x=-7+2*45/14
x=(-49+45)/7=-4/7

z=3*(-4/7)+45/14=3/2</PRE>