document.write( "Question 855017: You are given the information that triangle ABC has an altitude of CD. Then you have to write a paragraph proof stating that the Sin A/a = Sin B/b. \n" ); document.write( "
Algebra.Com's Answer #515056 by KMST(5328)\"\" \"About 
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If angles A and B are acute, altitude CD divides the triangle, into two right triangles:
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\n" ); document.write( "In those right triangles, the trigonometric ratios involving altitude CD and angles A and B are
\n" ); document.write( "\"sin%28A%29=CD%2Fb\"<-->\"CD=b%2Asin%28A%29\"
\n" ); document.write( "\"sin%28B%29=CD%2Fa\"<-->\"CD=a%2Asin%28B%29\"
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\n" ); document.write( "If one of the angles A and B is obtuse, sides AC and BC, along with altitude CD, and the line containing AB form two right triangles:
\n" ); document.write( " Ray BD is the extension of AB. Obtuse angle ABC is called angle B for short.
\n" ); document.write( "Angle B and angle CBD are supplementary and therefore have the same sine.
\n" ); document.write( "In right triangles ADC and BDC, the trigonometric ratios involving altitude CD and angles A and B are
\n" ); document.write( "\"sin%28A%29=CD%2Fb\"<-->\"CD=b%2Asin%28A%29\"
\n" ); document.write( "\"sin%28B%29=sin%28CBD%29=CD%2Fa\"<-->\"CD=a%2Asin%28B%29\"
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\n" ); document.write( "In either case, \"CD=b%2Asin%28A%29\" and \"CD=a%2Asin%28B%29\" ,
\n" ); document.write( "so \"b%2Asin%28A%29=a%2Asin%28B%29\"
\n" ); document.write( "Dividing both sides of the equal sign by \"ab\" we get
\n" ); document.write( "\"sin%28a%29%2Fa=sin%28B%29%2Fb\"
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