2x-3y=-29
3x+y=-16
------------------
2x-3y=-29
y=-3x-16
-----------------
2x-3(-3x-16)=-29
y=-3x-16
----------------------------
2x+9x+48=-29
y=-3x-16
--------------------
11x=-77
y=-3x-16
---------------------
x=-7
y=-3.(-7)-16
---------------------
x=-7
y=5
----------------------
/x,y/=/-7,5/
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