document.write( "Question 1210173: Let P be a point chosen uniformly at random inside triangle ABC. Extend ray BP to hit side AC at D. What is the probability that BD < 4?\r
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\n" ); document.write( "\n" ); document.write( "The sides of triangle ABC are 3, 5, and 7. \n" ); document.write( "
Algebra.Com's Answer #851600 by McCravyE(1)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "My question to Ikleyn is:\r\n" );
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document.write( "How do you know this:\r\n" );
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document.write( "The ratio of the area of triangle BAD' to the area of triangle BAC, equals the ratio of the length AD' to AC.\r\n" );
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document.write( "What theorem shows this is true? \r\n" );
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document.write( "You didn't state any theorem that shows that. And it certainly is not obvious\r\n" );
document.write( "to me.\r\n" );
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document.write( "Thanks for answering how you knew this to be true on your solution.\r\n" );
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document.write( "Edwin

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