document.write( "Question 453480: In Triangle ABC, A= 42 degrees, B= 68 degrees, and c= 15. Find the length of a and b
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Algebra.Com's Answer #311573 by pedjajov(51)\"\" \"About 
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If we draw a height h from vertex C it divides side c in point D into two pieces x=AD and y=BD
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\n" ); document.write( "Also it forms two right triangles:
\n" ); document.write( "- triangle ADC with one leg being height other one being x and b for hypotenuse
\n" ); document.write( "- triangle BDC with one leg being height other one being y and a for hypotenuse
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\n" ); document.write( "We have for x, y and c:
\n" ); document.write( "x+y=c -> x+y=15 -> x=15-y
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\n" ); document.write( "In triangle ADC we have \"tan%2842%29=h%2Fx\" -> \"h=x%2Atan%2842%29\"
\n" ); document.write( "In triangle BDC we have \"tan%2868%29=h%2Fy\" -> \"h=y%2Atan%2868%29\"
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\n" ); document.write( "Now we have -> \"x%2Atan%2842%29=y%2Atan%2868%29\"
\n" ); document.write( "If we substitute x with x=15-y we have:
\n" ); document.write( "\"%2815-y%29%2Atan%2842%29=y%2Atan%2868%29\"
\n" ); document.write( "\"15%2Atan%2842%29-y%2Atan%2842%29=y%2Atan%2868%29\"
\n" ); document.write( "\"15%2Atan%2842%29=y%2Atan%2842%29%2By%2Atan%2868%29\"
\n" ); document.write( "\"y=15%2Atan%2842%29%2F%28tan%2842%29%2Btan%2868%29%29\"
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\n" ); document.write( "From here:
\n" ); document.write( "\"x=15-y\"
\n" ); document.write( "\"x=15%2Atan%2868%29%2F%28tan%2842%29%2Btan%2868%29%29\"
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\n" ); document.write( "Knowing x we can find b=AC:
\n" ); document.write( "\"cos%2842%29=x%2Fb\"
\n" ); document.write( "\"b=x%2Fcos%2842%29\"
\n" ); document.write( "\"b=15%2Atan%2868%29%2Fcos%2842%29%28tan%2842%29%2Btan%2868%29%29\"
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\n" ); document.write( "b=14.80
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\n" ); document.write( "Knowing y we can find c=BC:
\n" ); document.write( "\"cos%2868%29=y%2Fc\"
\n" ); document.write( "\"c=y%2Fcos%2868%29\"
\n" ); document.write( "\"c=15%2Atan%2842%29%2Fcos%2868%29%28tan%2842%29%2Btan%2868%29%29\"
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\n" ); document.write( "c=10.68
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