document.write( "Question 1193627: Given:
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document.write( "△ABC with m∠A = 45°, m∠B = 30°, and
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document.write( "BC = 14
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document.write( "Find: AB
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document.write( "Draw altitude
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document.write( "CD
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document.write( " from C to
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document.write( "AB.
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document.write( " Determine the measures of ∠DCA and ∠DCB in degrees.
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document.write( "m∠DCA =
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document.write( " °
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document.write( "m∠DCB =
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document.write( " °
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document.write( "Find the exact lengths of
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document.write( "CD, AD, and DB.
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document.write( "CD =
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document.write( "
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document.write( "AD =
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document.write( "
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document.write( "DB =
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document.write( "Find AB. Give both an exact solution and an approximate solution to two decimal places.
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document.write( "exact AB =
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document.write( "approximate AB =
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Algebra.Com's Answer #825678 by Boreal(15235)![]() ![]() You can put this solution on YOUR website! a/sin A=c/sin C and angle C is 105deg. Side c is AB. \n" ); document.write( "14/sin45=x/sin 105 \n" ); document.write( "x=14*sin 105/sin45 \n" ); document.write( "=19.12 \n" ); document.write( "- \n" ); document.write( "Altitudes are perpendicular so triangle ADC is a right triangle and angle DCA is 45 degrees and angle DCB is 60 degrees. \n" ); document.write( "- \n" ); document.write( "Get AC or side b as well: 14/sin 45=b/sin 30 \n" ); document.write( "sin 30 is 0.5 \n" ); document.write( "b=14 sin30/sin45=7/sqrt(2)/2 or 7 sqrt(2)=9.90, which is the hypotenuse. \n" ); document.write( "The legs are each hyp/sqrt(2) or 7 The altitude is 7 \n" ); document.write( "That is also AD \n" ); document.write( "So DB is 12.12 \n" ); document.write( "the right triangles are 7/7/9.9 and 12.12/7/14\r \n" ); document.write( "\n" ); document.write( "- \n" ); document.write( "AD=x and DB is 19.12-x \n" ); document.write( "ACD is a right triangle, so x^2+alt^2=7^2=49 \n" ); document.write( "(19-x)^2+49=196 \n" ); document.write( "(19-x)^2=147 \n" ); document.write( "19-x=12.12 AB approx \n" ); document.write( "the exact value is sqrt(147)AB exact\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |