Question 145960
{{{y>6x}}} Start with the 1st inequality



{{{y=6x}}} Replace the inequality sign with an equals sign



So in order to plot {{{y>6x}}}, we need to plot the equation {{{y=6x}}} first



{{{ graph( 500, 500, -10, 10, -10, 10,6x) }}} Graph of {{{y=6x}}}



Now lets pick a test point, say (0,1). Any point will work, (just make sure the point doesn't lie on the line) but this point is the easiest to work with. Now evaluate the inequality {{{-6x+y>0}}} with the test point


Substitute (0,1) into the inequality


{{{(1)>6(0)}}} Plug in {{{x=0}}} and {{{y=1}}}


{{{1>0}}} Simplify




(note: for some reason, some of the following images do not display correctly in Internet Explorer. So I recommend the use of <a href=http://www.mozilla.com/en-US/firefox/>Firefox</a> to see these images.)



Since this inequality is true, we simply shade the entire region that contains (0,1)

{{{drawing( 500, 500, -20, 20, -20, 20,
graph( 500, 500, -20, 20, -20, 20,6x),
graph( 500, 500, -20, 20, -20, 20,6x,6x+5),
graph( 500, 500, -20, 20, -20, 20,6x,6x+10),
graph( 500, 500, -20, 20, -20, 20,6x,6x+15),
graph( 500, 500, -20, 20, -20, 20,6x,6x+20),
graph( 500, 500, -20, 20, -20, 20,6x,6x+25),
graph( 500, 500, -20, 20, -20, 20,6x,6x+30),
graph( 500, 500, -20, 20, -20, 20,6x,6x+35),
graph( 500, 500, -20, 20, -20, 20,6x,6x+40),
graph( 500, 500, -20, 20, -20, 20,6x,6x+45),
graph( 500, 500, -20, 20, -20, 20,6x,6x+50),
graph( 500, 500, -20, 20, -20, 20,6x,6x+55),
graph( 500, 500, -20, 20, -20, 20,6x,6x+60),
graph( 500, 500, -20, 20, -20, 20,6x,6x+65),
graph( 500, 500, -20, 20, -20, 20,6x,6x+70),
graph( 500, 500, -20, 20, -20, 20,6x,6x+75),
graph( 500, 500, -20, 20, -20, 20,6x,6x+80))}}}


Graph of {{{y>6x}}} with the boundary (which is the line {{{y=6x}}} in red) and the shaded region (in green) 
(note: since the inequality contains a greater-than sign, this means the boundary is excluded. This means the solid red line is really a dashed line)