Plotting 2D Graph in Mathematica: y>=340 & y<340

[James Wine]

If someone could supply the code to plot this graph in Mathematica would be awesome.

Would also be best if it checked the y's at units of t {0,1,2,3...,inf}

y >= 340
Plot[100 (t) - 340 (t/2), {t, 0, 20}]
y< 340
Plot[100 (t) - 115 (t/2) , {t, 0, 20}]

 

[Bill Simpson]

Plot3D[Piecewise[{{100 t-340 t/2, y>=340}, {100 t-115 t/2, y<340}}], {t, 0, 20}, {y, 0, 1000}]

but that does not graph y to infinity.

 

[James Wine]

Thank you, sadly I won't be able to check it until i get home. On the road working.