document.write( "Question 265854: Tony needs a glass bell jar in the shape of a cylinder with a hemisphere on top. The height of the cylinder must be 3 inches longer than its radius and the volume must be 72pi cubic inches. What should the radius of the cylinder be?\r
\n" ); document.write( "\n" ); document.write( "The name of the lesson is Fundamental Theorem of Algebra.
\n" ); document.write( "Do i need to find the roots to get the radius?
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Algebra.Com's Answer #195605 by ankor@dixie-net.com(22740)\"\" \"About 
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Tony needs a glass bell jar in the shape of a cylinder with a hemisphere on top. The height of the cylinder must be 3 inches longer than its radius and the volume must be 72pi cubic inches. What should the radius of the cylinder be?
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\n" ); document.write( "Let r = the radius of the cylinder (and the hemisphere)
\n" ); document.write( "then
\n" ); document.write( "(r+3) = the height of the cylinder
\n" ); document.write( ":
\n" ); document.write( "vol of a sphere =\"%284%2F3%29pi%2Ar%5E3\", therefore
\n" ); document.write( "vol of a hemisphere = \"%282%2F3%29pi%2Ar%5E3\"
\n" ); document.write( ":
\n" ); document.write( "vol of cylinder + vol of hemisphere = 72*pi
\n" ); document.write( "\"pi%2Ar%5E2%2Ah\" + \"%282%2F3%29pi%2Ar%5E3\" = \"72pi\"
\n" ); document.write( ":
\n" ); document.write( "Divide thru by pi and eliminate that
\n" ); document.write( "\"r%5E2%2Ah\" + \"%282%2F3%29%28r%5E3%29\" = 72
\n" ); document.write( ":
\n" ); document.write( "Replace h with (r+3)
\n" ); document.write( "\"r%5E2%2A%28r%2B3%29\" + \"%282%2F3%29r%5E3\" = 72
\n" ); document.write( ":
\n" ); document.write( "\"r%5E3%2B3r%5E2%29\" + \"%282%2F3%29r%5E3\" = 72
\n" ); document.write( ":
\n" ); document.write( "Add like terms r^3 + 2/3*r^3
\n" ); document.write( "\"%285%2F3%29%28r%5E3%29\" + \"3r%5E2\" = 72
\n" ); document.write( ":
\n" ); document.write( "Multiply each term by 3
\n" ); document.write( "\"5r%5E3+%2B+9r%5E2\" = 216
\n" ); document.write( ":
\n" ); document.write( "\"5r%5E3+%2B+9r%5E2+-+216\" = 0
\n" ); document.write( ":
\n" ); document.write( "Graph this equation, find x intercept
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-4%2C+10%2C+-100%2C+300%2C+5x%5E3%2B9x%5E2-216%29+\"
\n" ); document.write( "r = 3 inches the radius
\n" ); document.write( ":
\n" ); document.write( "Check; find the volumes
\n" ); document.write( "\"pi%2A3%5E2%2A6\" = 169.646
\n" ); document.write( "\"%282%2F3%29pi%2A3%5E3\" = 56.487
\n" ); document.write( "--------------------
\n" ); document.write( "Total volume is 226.195 divide this by pi you have 71.999 ~ 72
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