How do I draw a cross-section through a 3D object?

[annalian]

Homework Statement

http://3.1m.yt/J986z5A.jpg

Homework Equations

The Attempt at a Solution

I don't know if this is a cross section or if I should draw it. Could you give me a any other example or hint a bout this exercise? I think it can be a triangle, but I am not sure. i don't know how to add the lines or draw the section.

 

[berkeman]

Please read the tutorials posted in your other thread. When you are ready to show some work on this new problem, send me a PM and I'll re-open this thread so you can show your work.

Your other thread with the tutorials is here: https://www.physicsforums.com/threads/can-you-explain-this-cross-cut.895493/#post-5633237