Geometry: An Interactive Journey to Mastery

x volume and surface area of a sphere
V =^43 ʌU^3.
total surface area = 4ʌU^2.
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Summary
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three-dimensional shapes and develop formulas for their surface areas and volumes.
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Derive a formula for the surface area of a right circular cylinder with height h and
base radius rͼ௘6HH)LJXUH௘ͽ
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We can image a cylinder as constructed by rolling a rectangular
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7KHODWHUDODUHDRIWKHF\OLQGHULVWKXVʌUh, and its total surface area is
222.SSS S Srh r^22 r rh r^2

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A cone has a regular hexagon with side length 6 inches for its base. Each lateral edge of the cone has length
10 inches.
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