Find the height $ h $ of a cone if radius $r = 7$ and slant height $l = 19$.
Answer
$h = 2 \sqrt{ 78 }$
Explanation
To find side $ h $ use Pythagorean Theorem:
$$ r^2 + h^2 = l^2 $$After substituting $ r = 7 $ and $ l = 19 $ we have:
$$ 7^2 + h^2 = 19^2 $$ $$ h^2 = 19^2 - 7^2 $$ $$ h^2 = 361 - 49 $$ $$ h^2 = 312 $$ $$ h = \sqrt{ 312 } $$$$ h = 2 \sqrt{ 78 } $$This page was created using
Cone Calculator