The Surface Area of a Right Circular Cylinder of Height $S = \pi r ^ { 2 } + 18 \pi r$

question 33

Multiple Choice

The surface area of a right circular cylinder of height 9 units is given by $S = \pi r ^ { 2 } + 18 \pi r$ . Factor this expression.

• A) \(r ^ { 2 } ( \pi + 18 r )\)
• B) \(r ( r + 18 \pi )\)
• C) \(\pi r ( r + 18 )\)
• D) \(r ^ { 2 } ( \pi + 18 )\)
• E) \(\pi \left( r ^ { 2 } + 18 \right)\)

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