triangle cube

Is their a quick way to make a triangular prism shape ( this is half a cube).
I removed a from the cube but that didnt work.

What I want to do is make a simple house shape. A cube with roof on top.

I can cut a cube in half by merging at center points on the cube but then aligning 2 shapes on top of each other.

Piece of cake! Take your cube and rotate the view with MMB so that you can see all verts. Then on one side of the cube select two verts opposite of each other on the diagonal and Fkey to draw an edge between them. Do the same for the other side of the cube. Then select the two verts of the part of the cube you don’t want and Xkey them. Voila! A cube cut in half!

i have bl 2.5 and how do i draw an edge . i know what you mean to do I just dont know how to draw a line.

>Fkey to draw an edge between them?

sorry yes F key . I am thinking a function key.
Anyway to make a house I use extrude, merged center on some points and cam up with the model

There are really dozen of ways to create roof geometry. Here is one way (Jagguy2 beat me to it).

Make a rectangle (main shape of house). Extrude top face, select top two vertices (image 1 and circle around the vertices), and merge those points at their center. Do that for the back too to make the simple roofline.

As for making an edge, what you do is to select a vertex then hit “E” key to extrude that vertex. New vertex forms and as you drag the vertex new edge is created.