7th Grade · Geometry
Cross-Section
7.G.A.3
Definition
The two-dimensional shape formed when a flat plane intersects a three-dimensional solid. The shape depends on the solid and the angle of the cut.
Examples
- A rectangular prism sliced parallel to its base gives a rectangle.
- A cone or sphere sliced through the center gives a circle.
Key rule
Slicing at an angle can produce a different shape than slicing straight across.
Memory hook
Slice the solid — what shape do you see?