Question #567b4

1 Answer
Dec 24, 2017

See a solution process below:

Explanation:

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The height, slant height and radius of a cone make up a right triangle as seen above.

The Pythagorean Theorem states;

#a^2 + b^2 = c^2# where #c# is the hypotenuse of a right triangle.

In this case:

#r^2 + h^2 = l^2#

Solving for #r# gives:

#r^2 + h^2 - color(red)(h^2) = l^2 - color(red)(h^2)#

#r^2 + 0 = l^2 - h^2#

#r^2 = l^2 - h^2#

#sqrt(r^2) = sqrt(l^2 - h^2)#

#r = sqrt(l^2 - h^2)#