3x-y=7
4x+6y=2
--------------------------
y=3x-7
2x+3y=1
------------------
y=3x-7
2x+3(3x-7)=1
---------------------
y=3x-7
2x+9x-21=1
---------------------------
y=3x-7
11x=22
--------------------
y=3x-7
x=2
----------------
y=3.2-7=6-7=-1
x=2
--------------------------
/x,y/=/2,-1/
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