Cross Sections of Solids
Aligned to 7.G.A.3 — Common Core State Standards for Mathematics.
What this lesson teaches
Slicing a 3-D solid with a flat plane produces a 2-D cross section. The shape depends on the solid and the angle of the cut. A cut parallel to a face usually matches that face's shape.
Worked example
Slice a right rectangular prism with a plane parallel to its base. The cross section is a rectangle the same size and shape as the base.
Practice questions
- What cross section results from slicing a cube parallel to one of its faces?
- A right rectangular pyramid is sliced parallel to its base. Name the cross-section shape.
- Describe the cross section when a cylinder is sliced parallel to its base.
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Secciones Transversales de Sólidos
Cortar un sólido de 3 dimensiones con un plano produce una sección transversal de 2 dimensiones. La forma depende del sólido y del ángulo del corte. Un corte paralelo a una cara suele tener la misma forma que esa cara.
Ejemplo: Corta un prisma rectangular recto con un plano paralelo a su base. La sección transversal es un rectángulo del mismo tamaño y forma que la base.
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