Geometry: An Interactive Journey to Mastery

Three-Dimensional Geometry—Solids

Lesson 23

Topics
x Names of three-dimensional shapes.
x Cavalieri’s principle and the volume cylinders.
x The volumes and surface areas of cylinders, cones, and spheres.
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ż selecting a point PDQ\ZKHUHDERYHRUEHORZWKHSODQHͼ௘7KLVZLOO
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ż drawing a line segment from each and every point on the boundary
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connecting, with straight line segments, matching boundary
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segments are parallel.
If the line segments connecting matching boundary points are perpendicular to the planes containing
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x prism: A cylinder with a polygon for its base.
x pyramid: A cone with a polygon for its base.

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Figure 23.1

oblique right

Figure 23.2