Describe Cross-Sections of 3D Figures - 7th Grade Math

What $2$ D figure results when a right rectangular prism is sliced perpendicular to its base?

A rectangle. Perpendicular cuts through a prism create rectangles.
Identify the cross section: slice a right rectangular pyramid parallel to its base.

A rectangle. Parallel cuts preserve base shape but reduce size.
Which $2$ D figure can result when a right rectangular prism is sliced by a slanted plane not parallel to any face?

A parallelogram. Slanted cuts through opposite edges create parallelograms.
Identify the cross section: slice a right rectangular prism parallel to the base.

A rectangle. Parallel cuts preserve the base shape.
Which $2$ D figure is impossible from slicing a right rectangular pyramid: rectangle, trapezoid, or circle?

Circle. Pyramids have straight edges, so no curved cross sections.
Identify the cross-section of a right rectangular prism cut parallel to a lateral face.

A rectangle. Cutting parallel to any face reproduces that face's shape.
Which cross section is possible for a right rectangular pyramid: square, rectangle, or circle?

Rectangle. Pyramids with rectangular bases can have rectangular cross sections.
Identify the cross section: slice a right rectangular pyramid with a plane through the apex and base center.

A triangle. Vertical cuts through apex create triangular sections.
Identify the cross section: a diagonal plane cuts a right rectangular prism and intersects $4$ lateral edges.

A parallelogram. Four-sided figures result when cutting through 4 edges.
Identify the cross-section of a right rectangular prism cut by a plane parallel to the base at mid-height.

A rectangle. Parallel cuts through prisms maintain the base shape.
What $2$ D figure results when a right rectangular pyramid is sliced by a plane that cuts all $4$ lateral faces?

A quadrilateral. Cutting all 4 lateral faces creates a 4-sided figure.
What $2$ D figure results when a right rectangular pyramid is sliced parallel to its base?

A rectangle similar to the base. Parallel cuts to pyramid bases create similar, not congruent shapes.
What is a right rectangular pyramid (in words, not a formula)?

A pyramid with a rectangular base and apex above the base center. "Right" means the apex is directly above the base's center.
Identify the cross-section of a right rectangular prism cut parallel to its base.

A rectangle (congruent to the base). Parallel cuts preserve the base shape and size.
Identify the cross section: a right rectangular pyramid is cut by a plane perpendicular to the base and not through the apex.

Trapezoid. Perpendicular cuts missing the apex form trapezoids.
Identify the cross section: a right rectangular prism is cut by a plane parallel to the base.

Rectangle. Parallel cuts to prism bases preserve the base shape.
What $2$ D figure results when a right rectangular pyramid is sliced perpendicular to its base through the apex?

A triangle. Cuts through the apex create triangular cross sections.
Identify the cross section of a cube sliced parallel to one face.

A square. A cube's faces are squares, so parallel cuts yield squares.
Identify the cross section: a right rectangular pyramid is cut by a plane through the apex and perpendicular to the base.

Triangle. Vertical cuts through pyramid apex create triangles.
Identify the cross-section of a right rectangular prism cut perpendicular to its base.

A rectangle. Any perpendicular cut through a prism creates a rectangle.
What is the name of the 2D figure formed by slicing a solid with a plane?

A cross section (plane section). The intersection of a plane and a 3D solid creates a 2D figure.
What 2D shape results from slicing a right rectangular pyramid perpendicular to its base through the apex?

A triangle. Vertical cuts through apex create triangular sections.
What is the name of the $2$ D figure formed by the intersection of a plane and a solid?

A cross section (a plane section). The intersection of a plane with a 3D solid creates a 2D shape.
What is a right rectangular prism (in words, not a formula)?

A prism with rectangular bases and lateral edges perpendicular to bases. "Right" means edges are perpendicular; it's a box shape.
What is a plane section (cross-section) of a solid?

The $2$ D shape formed where a plane slices a $3$ D solid. The plane cuts through the solid, creating a flat shape.
What is the most common cross section shape for both right rectangular prisms and right rectangular pyramids?

A rectangle. Both solids frequently produce rectangular cross sections.
Which cross section is possible for a right rectangular prism: triangle, circle, or rectangle?

Rectangle. Prisms can't have triangular cross sections unless cut diagonally.
Which $2$ D shape results from a right rectangular pyramid sliced by a plane that cuts the base but misses the apex?

A trapezoid. Missing the apex creates parallel sides (trapezoid).
Which $2$ D figure is impossible from slicing a right rectangular prism: circle, rectangle, or parallelogram?

Circle. Prisms have straight edges, so no curved cross sections.
Choose the correct statement: A plane section is $2$ D, and the solid being sliced is $3$ D.

True. Cross-sections are flat ( $2$ D) slices of $3$ D objects.
What 2D shape results from slicing a right rectangular pyramid parallel to its base?

A rectangle (similar to the base). Parallel cuts create similar shapes, smaller near apex.
What is always true about a cross section made parallel to a face of a right rectangular prism?

It is congruent to that face. Parallel cuts produce exact copies of prism faces.
Which 2D shape results from slicing a right rectangular prism parallel to its base?

A rectangle (congruent to the base). Parallel cuts preserve the shape and size of the base.
Which term best describes a slice that meets the base at a $90^\circ$ angle?

Perpendicular to the base. Forms a right angle with the base plane.
What is always true about a cross section made parallel to the base of a pyramid?

It is similar to the base. Parallel cuts maintain shape ratios but change size.
Identify the cross section of a cube sliced through the center, perpendicular to the base.

A rectangle. Perpendicular cuts through a cube create rectangles.
What $2$ D shape results when a plane slices a right rectangular prism through all $4$ lateral faces?

A quadrilateral. Cutting all 4 lateral faces creates 4 intersection points.
Identify the cross-section of a right rectangular pyramid cut parallel to its base.

A rectangle (similar to the base). Parallel cuts create proportionally smaller rectangles.
Identify the cross-section of a right rectangular pyramid cut through the apex and perpendicular to the base.

A triangle. Vertical cuts through the apex create triangular sections.
Which 2D shape results from slicing a right rectangular prism perpendicular to its base?

A rectangle. Perpendicular cuts through prisms create rectangles.
Which 2D shape can result from a diagonal slice through a right rectangular prism?

A parallelogram. Diagonal cuts create parallelograms when intersecting 4 edges.
Which $2$ D shape results from a right rectangular pyramid sliced by a plane that intersects $3$ lateral faces but not the base?

A triangle. Three lateral faces meet at three edges, forming a triangle.
Which term best describes a slice that never meets the base and stays the same distance from it?

Parallel to the base. Maintains constant distance from the base plane.
What $2$ D figure results when a right rectangular prism is sliced parallel to one lateral face?

A rectangle congruent to that face. Parallel cuts to any face preserve that face's shape and size.
What $2$ D figure results when a right rectangular pyramid is sliced perpendicular to its base but not through the apex?

A trapezoid. Perpendicular cuts not through apex create 4-sided figures.
Which option is always true for a pyramid cut parallel to its base: congruent or similar cross-section?

Similar. Pyramids taper, so parallel cuts are smaller but same shape.
Which statement is true for a prism slice parallel to the base: congruent or similar to the base?

Congruent to the base. Prisms have uniform cross sections, so cuts are congruent.
Which 2D shape results from slicing a right rectangular prism parallel to a lateral face?

A rectangle (congruent to that face). Parallel cuts to any face produce congruent copies.
Identify the cross section: a cube is cut by a plane parallel to a face.

Square. Cube faces are squares; parallel cuts preserve this shape.
What $2$ D figure results when a right rectangular prism is sliced parallel to its base?

A rectangle congruent to the base. Parallel cuts preserve shape and size of the base.
Identify the cross section: slice a right rectangular prism perpendicular to the base.

A rectangle. Perpendicular cuts create rectangles in prisms.
Identify the cross section: a right rectangular pyramid is cut by a plane parallel to the base.

Rectangle. Pyramid slices parallel to base are similar rectangles.
Which $2$ D shape results from a right rectangular pyramid sliced by a plane that intersects all $4$ lateral faces but not the base?

A quadrilateral. Four lateral faces create four intersection points.
Which option is always true for a prism cut parallel to its base: congruent or similar cross-section?

Congruent. Prisms have uniform width, so parallel cuts are identical.
Identify the cross section: slice a cube parallel to any face.

A square. All faces of a cube are congruent squares.
Which statement is true for a pyramid slice parallel to the base: congruent or similar to the base?

Similar to the base. Pyramids taper, so parallel cuts create smaller similar shapes.
Identify the cross-section of a right rectangular pyramid cut by a plane that contains one base edge and the apex.

A triangle. The plane contains 3 points: 2 base vertices and the apex.

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