University:
Missouri State University
Course:
MTH 460 | College Geometry
Academic year:

2019
Views:

477

Pages:

3
Author:

Maverick Haynes

MATH 7 NAME Ney PERIOD UNIT 5 CROSS SECTIONS DATE A geometric plane is a two-dimensional figure that goes on and on in both directions without end. Think of it as a sheet of paper that never ends. The two-dimensional shape that is made by slicing through a three-dimensional figure, using a plane, is called a Cross section plane section or a The examples below show some of the cross sections that can be made by slicing a right rectangular prism with a plane. Example 1 Parallel planes are planes that do not intersect. Think of the floor and the ceiling of a room as parallel planes When a geometric plane slices a prism so that the cut is parallel to the plane of the base, the cross section will have the shape of the base. So, in the case of a right rectangular prism, the cross section is a rectangle. Example 2 Perpendicular planes are planes that meet at right angles. Think of the floor and a wall of a room as perpendicular planes. If the cut is perpendicular to the base and parallel to one pair of lateral (side) faces, the cross section will be a rectangle that has the same shape as the lateral face. A right rectangular pyramid is a three-dimensional figure that has a rectangular base and three triangular faces that meet at a point called the center of the base. vertey It is positioned exactly above the The examples below show some of the cross sections that can be made by slicing a right rectangular pyramid with a plane. Example 1 When a geometric plane slices any right pyramid so that the cut is parallel to the plane of the base, the cross section will have the same shape (but not the same size) as the base. So, in the case of a right rectangular pyramid, the cross section is a rectangle. Example 2 If the cut is perpendicular to the base and passes through the vertex, the cross section will be an isosceles triangle WRITE THE BEST NAME FOR THE CROSS SECTION OF EACH SOLID FIGURE. "pectingle 2 triangle 3) pectangle 4) square 5) tree agle 6) Circle 7) cude A cone is cut parallel to its base. 8 ) pectangle A figure in the shape of a shoebox is cut parallel to its base. pectangle A cylinder is cut perpendicular to its base. TRY THE FOLLOWING ON YOUR OWN: B 9) Which two-dimensional shape describes the shape of a horizontal slice through the soccer ball? A) oval B) circle C) rectangle D) square 10) When sliced vertically, which solid figures would produce a rectangle? Circle all correct answers. (HINT: Prisms MUST be standing on their bases!!!) a. b. d. 11) Draw the two-dimensional figure that would describe a vertical cut through this figure. It would be a kectangle 12) Which of these solid figures, when sliced horizontally, would produce a cross section in the shape of a circle? Circle all correct answers. a. b. d. 13) Which two-dimensional shape describes the shape of a horizontal slice through this figure (whose base has a 1-meter length and a 0.75-meter width)? a. b. C. d.