Question

Maximize P=3x+2y
subject to 6x+3y<=24
3x+6y=<30
X,Y>=10

Answer 1

That x,y>=10 is a killer.
Removing that, we get a max at
p(2,4) = 14

A good online tool is at

http://www.zweigmedia.com/RealWorld/LPGrapher/lpg.html