Question 167519
X=2Y-4
X+Y<=50
(2Y-4)+Y<=50
3Y-4<=50
3Y<=50+4
3Y<=54
Y<=54/3
Y<=18
X=2*18-4
X=36-4
X=32 
PROOF:
LET Y=17.9
32+17.9<=50
49.9<=50