Question
Find the lateral area $ AL $ of a cylinder if diameter $d = 20\, \text{cm}$ and height $h = 23\, \text{cm}$.
Answer
$460\pi\, \text{cm}^2$
Explanation
STEP 1: find radius $ r $
To find radius $ r $ use formula:
$$ d = 2 \cdot r $$After substituting $d = 20\, \text{cm}$ we have:
$$ 20\, \text{cm} = 2 \cdot r $$ $$ r = \dfrac{ 20\, \text{cm} }{ 2 } $$ $$ r = 10\, \text{cm} $$STEP 2: find lateral area $ AL $
To find lateral area $ AL $ use formula:
$$ AL = 2 \cdot h \cdot r \cdot \pi $$After substituting $r = 10\, \text{cm}$ and $h = 23\, \text{cm}$ we have:
$$ AL = 46\, \text{cm} \cdot 10\, \text{cm} \cdot \pi $$$$ AL = 460\pi\, \text{cm}^2 $$This page was created using
Cylinder Calculator