document.write( "Question 46596: A 3-foot pole casts a shadow of 9 feet. How tall is a tree with a shadow of 12 feet?\r
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Algebra.Com's Answer #30884 by AnlytcPhil(1806)\"\" \"About 
You can put this solution on YOUR website!
A 3-foot pole casts a shadow of 9 feet.\r\n" );
document.write( "How tall is a tree with a shadow of 12 feet? \r\n" );
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document.write( "Let x represent the height of the tree.\r\n" );
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document.write( "The proportion is:\r\n" );
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document.write( "     TREE             POLE \r\n" );
document.write( "-------------- = --------------\r\n" );
document.write( "SHADOW OF TREE   SHADOW OF POLE\r\n" );
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document.write( "          x     3\r\n" );
document.write( "        ---- = ---\r\n" );
document.write( "         12     9\r\n" );
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document.write( "Cross-multiply:\r\n" );
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document.write( "UPPER LEFT × LOWER RIGHT = LOWER LEFT × UPPER RIGHT\r\n" );
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document.write( "         9x = 36\r\n" );
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document.write( "          x = 4 feet\r\n" );
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document.write( "That's a very short tree!-- just a sapling! With a \r\n" );
document.write( "tree that short it would have been much easier for\r\n" );
document.write( "them just to have measured the tree than to have \r\n" );
document.write( "measured the pole and the two shadows and then\r\n" );
document.write( "done the above algebra!!!\r\n" );
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document.write( "Edwin
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