Find the area $ A $ of a cylinder if radius $r = 8.7$ and height $h = 18.9$.

$A = 480.24$

STEP 1: find base area $ AB $

To find base area $ AB $ use formula:

$$ AB = r^2 \cdot \pi $$

After substituting $ r = 8.7 $ we have:

$$ AB = 8.7^2 \cdot \pi $$ $$ AB = 75.69 \cdot \pi $$

STEP 2: find lateral area $ AL $

To find lateral area $ AL $ use formula:

$$ AL = 2 \cdot r \cdot h \cdot \pi $$

After substituting $ r = 8.7 $ and $ h = 18.9 $ we have:

$$ AL = 17.4 \cdot 18.9 \cdot \pi $$$$ AL = 328.86\pi $$

STEP 3: find area $ A $

To find area $ A $ use formula:

$$ A = 2 AB + AL $$

After substituting $ AB = 75.69\pi $ and $ AL = 328.86\pi $ we have:

$$ A = 2 \cdot 75.69\pi + 328.86\pi $$ $$ A = 151.38 + 328.86 $$ $$ A = 480.24 $$

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