I know! It's kind if annoying tbh...
The given equation is

Here we have to solve for n. First we need to get rid of the denominators and for that we do cross multiplication .

Now we need to isolate n. And for that we need to get rid of 12, by dividing both sides by 12



And that's the required value of n .
Answer:
You are correct that the cross section is a rectangle, because a rectangular pyramid has 4 sides connected to the top of the rectangle.
Step-by-step explanation: