document.write( "Question 4265: The height of a cylinder is four times its radius. Find a function that models the volume V of the cylinder in terms of its radius r. I know that V=pir^2h, but I don't understand how to write a function when the height of a cylinder is four times its radius. Thanks \n" ); document.write( "
Algebra.Com's Answer #327399 by cleomenius(959)\"\" \"About 
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From what I understand in terms of your questions, you are asking to have formula expressed in terms of r.\r
\n" ); document.write( "\n" ); document.write( "The formula for the right circular cylinder is V = ( pi * r^2) h\r
\n" ); document.write( "\n" ); document.write( "I will adjust this to put h in terms of r:
\n" ); document.write( "V = ( pi * r^2 ) 4r\r
\n" ); document.write( "\n" ); document.write( "V = 4 *Pi *r^3\r
\n" ); document.write( "\n" ); document.write( "This works to V/4 *pi = r^3\r
\n" ); document.write( "\n" ); document.write( "In terms of r, we should obtain r = the cubed root of V/ 4 * pi.\r
\n" ); document.write( "\n" ); document.write( "To check, I used a radius of 3 in the original formula to obtain the volume or 339.29\r
\n" ); document.write( "\n" ); document.write( "Working backwards from the cubed root of V/4 * pi, using 339.29 for V, I obtained a r of 3.\r
\n" ); document.write( "\n" ); document.write( "I think the equation you are looking for in this problem is r = cubed root of V / 4 * pi.\r
\n" ); document.write( "\n" ); document.write( "Cleomenius.
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