document.write( "Question 927493: Two sides of a triangle measure 80 cm and 64 cm. The area of the triangle is 2,262 cm. Find the third side. \n" ); document.write( "
Algebra.Com's Answer #563034 by Alan3354(69443)\"\" \"About 
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Two sides of a triangle measure 80 cm and 64 cm. The area of the triangle is 2,262 cm [sic] it's sq cm. Find the third side.
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\n" ); document.write( "Area = b*h/2
\n" ); document.write( "b = 80
\n" ); document.write( "A = angle between the given sides
\n" ); document.write( "h = 64*sin(A)
\n" ); document.write( "2262 = 80*64*sin(A)/2 = 2560*sin(A)
\n" ); document.write( "sin(A) = 2262/2560 =~ 0.883594
\n" ); document.write( "A =~ 62.1 degs
\n" ); document.write( "----
\n" ); document.write( "c = 3rd side
\n" ); document.write( "c^2 = a^2 + b^2 - 2abcos(A)
\n" ); document.write( "c^2 = 80^2 + 64^2 - 2*80*64*cos(62.1)
\n" ); document.write( "c^2 = 6400 + 4096 - 10240*0.468254 = ~5701
\n" ); document.write( "c = 75.5
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\n" ); document.write( "Check using Heron's Law
\n" ); document.write( "s = (80+64+75.5)/2 = 109.75
\n" ); document.write( "\"Area+=+sqrt%28s%28s-a%29%28s-b%29%28s-c%29%29\"
\n" ); document.write( "\"Area+=+sqrt%28109.75%2A29.75%2A45.75%2A34.25%29%29\"
\n" ); document.write( "Area = 2261.89
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\n" ); document.write( "It's surprising, I've been doing this stuff for 55 years or so, and never seen a problem like this one.
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