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Course: High school geometry>Unit 9

Lesson 1: 2D vs. 3D objects

Dilating in 3D

The cross sections of 3D shapes are dilations of the original shape, centered at a specific point. The scale factor of the dilation depends on the height of the cross-section or the distance from the point on the base.  Created by Sal Khan.

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• Would the dilations and cross sections look the same if you put the 3D pyramid on a coordinate plane?
• How can you put a 3D object such as a pyramid on a coordinate plane which is 2 dimensional? You could put it within a 3D space on an x-y-z coordinate system, but not a coordinate plane.
• hi, how are u
• I am doing quite well; thank you for asking!
I highly suggest that you use this place for asking math questions!
• Would it look the same if it was a 3D pyramid?
• I'm sorry, but a pyramid is always 3D, so your question makes no sense.
• im falling asleep
• So dont!
You must pay attention if you're going to learn anything from Sal!
• why does it keep asking for more questions
• هل يمكن لأي شخص أن يشرح لي هذا في فترة أسبوعين
• Would the dilations and cross sections look the same if you put the 3D pyramid on a coordinate plane
(1 vote)
• One, you copied @FemiO, two you can't put a 3D object on a coordinate plane.
• How do we know which dilation is a 0.5 or a 0.75?