document.write( "Question 733053: In the diagram of triangle ABC, side BC is extended to D\r
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Algebra.Com's Answer #448247 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
If \r
\n" ); document.write( "\n" ); document.write( "m< \"A=+x%5E2-6x\" ,
\n" ); document.write( "m< \"B=+2x-3\", and
\n" ); document.write( "m< \"ACD=+9x%2B27\",
\n" ); document.write( "what is the value of \"x\"?\r
\n" ); document.write( "\n" ); document.write( "recall:\r
\n" ); document.write( "\n" ); document.write( "The exterior angle theorem: the exterior angle of a triangle is equal to the sum of the two remote interior angles\r
\n" ); document.write( "\n" ); document.write( "so, m< \"ACD\"=m< \"A\"+ m< \"B\"\r
\n" ); document.write( "\n" ); document.write( "then you have\r
\n" ); document.write( "\n" ); document.write( "\"9x%2B27=x%5E2-6x%2B2x-3\"\r
\n" ); document.write( "\n" ); document.write( "\"9x%2B27=x%5E2-4x-3\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2-4x-9x-3-27=0\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2-13x-30=0\"...factor...replace \"-13x\" with \"-15x%2B2x\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2-15x%2B2x-30=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2-15x%29%2B%282x-30%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"x%28x-15%29%2B2%28x-15%29=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x%2B2%29%28x-15%29=0\"\r
\n" ); document.write( "\n" ); document.write( "so, if \"x%2B2=0\"...=>...\"x=-2\"....this solution make equation true, but it could not work with angle measure because it cannot be negative\r
\n" ); document.write( "\n" ); document.write( " if \"x-15=0\"...=>...\"x=15\"...so, your solution is:\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28x+=+15%29+\"\r
\n" ); document.write( "\n" ); document.write( "now find the measure of each angle:\r
\n" ); document.write( "\n" ); document.write( "m< \"A=+15%5E2-6%2A15\"...=>\"A=+225-90\"..=>\"A=+135\"
\n" ); document.write( "m< \"B=+2%2A15-3\"...=> \"B=30-3\"..=> \"B=27\"
\n" ); document.write( "m< \"ACD=+9%2A15%2B27\"...=>\"ACD=+135%2B27\"..=>\"ACD=+162\"\r
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