document.write( "Question 1037268: Given the points A (0,0), B (4,3) and C (2,9), what is the measure of angle< ABC? \n" ); document.write( "
Algebra.Com's Answer #651970 by Edwin McCravy(20063)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "His way will work, but it's much longer, and that's not \r\n" );
document.write( "the way you were taught to find the angle between two lines.\r\n" );
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document.write( "You find the slopes of AB and BC, m1 and m2,\r\n" );
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document.write( "then you use the formula for the acute angle between two lines:\r\n" );
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document.write( "\"tan%28theta%29\"\"%22%22=%22%22\"\"abs%28%28m%5B1%5D-m%5B2%5D%29%2F%281%2Bm%5B1%5Dm%5B2%5D%29%29\"\r\n" );
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document.write( "then find the inverse tangent.\r\n" );
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document.write( "From the looks of the graph, the angle you want ABC is obtuse so\r\n" );
document.write( "you find the acute angle between AB and BC and then find its\r\n" );
document.write( "supplement, which means you will subtract from 180°.\r\n" );
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document.write( "Answer: 108.4349488°\r\n" );
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document.write( "Edwin

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