Question 1117077
the formula {{{S= pi*r*sqrt(r^2+h^2)}}}. What is the height of this cone? 

S= 225 cm^2
r= 5 cm
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{{{225 = pi*5*sqrt(25 + h^2)}}}
Solve for h
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Now what?
2 "solutions," 2 different numbers.
You might have to do it, and learn how to do it.
Both of them show you how to do it.