Here is a method which gives you control over the curve.
If you need to be 100% accurate to the design you could load the image in the background and trace it.
[STEPS]
01. Using the Line tool (Shapes > Spline) - draw a Triangle and when prompted close the spline (note: I used Grid Snapping)
02. Under the Vertex rollout click Refine and add a new knot in the middle of the line
03. Select the newly created knot then right-click and convert it to a Bezier
04. Move the knot and adjust the handles so that you get the angle you're after (note: here is where a blueprint/reference may be handy)
--- also I set the Interpolation Steps to 10 and Optimized to create evenly spaces edges (as shown in image 05.)
05. Add the Extrude Modifier and enter a value in the amount, like shown (note: if you didn't close the spline then this would give unwanted results)
06. Add the Edit Poly Modifier and then right-click and Collapse All which gives you an Editable Poly object.
Hope this helps.
