5x+3y=4
2x-y=-5
---------------------
5x+3y=4
y=2x+5
------------------
5x+3(2x+5)=4
y=2x+5
-----------------------
5x+6x+15=4
y=2x+5
----------------------
11x=-11
y=2x+5
------------------
x=-1
y=2(-1)+5=-2+5=3
--------------------------
/x,y/=/-1,3/
===============