document.write( "Question 1108259: The perimeter of a right triangle is 144 cm. The base is 12 cm. less than the width. Find the area. \n" ); document.write( "
Algebra.Com's Answer #723287 by rapaljer(4671)\"\" \"About 
You can put this solution on YOUR website!
Let x = width
\n" ); document.write( "x-12 = base
\n" ); document.write( "c= hypotenuse
\n" ); document.write( "Perimeter = x + x-12 + c = 144
\n" ); document.write( "2x+c -12 = 144
\n" ); document.write( "2x+c= 156
\n" ); document.write( "c=156-2x\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Since it's a right triangle, \"a%5E2+%2B+b%5E2+=+c%5E2\"
\n" ); document.write( "\"x%5E2+%2B+%28x-12%29%5E2+=+%28156-2x%29%5E2\"
\n" ); document.write( "\"+x%5E2+%2B+x%5E2-24x+%2B+144+=+156%5E2+-+624x+%2B+4x%5E2+\"
\n" ); document.write( "\"2x%5E2+-24x+%2B144=+24336+-624x%2B4x%5E2\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"0=+2x%5E2-600x+%2B+24192\"
\n" ); document.write( "\"0=+x%5E2+-300x+%2B+12096\"\r
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\n" ); document.write( "\n" ); document.write( "Rewrite this to solve by completing the square \r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+-300+%2B+____=-12096+%2B+______\"
\n" ); document.write( "\"x%5E2+-+300+%2B+22500+=+-12096+%2B+22500\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"+%28x-150%29+%5E2+=+10404\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Take square root of both sides:
\n" ); document.write( "\"x-150=0+%2B-102\"
\n" ); document.write( "\"x=150+%2B-102\"\r
\n" ); document.write( "\n" ); document.write( "\"x=252\" or \"x=48\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The first answer is an extraneous root and must be rejected since the perimeter exceeds 144. The second answer gives legs of a right triangle to be 48 and 36, so the area is \"A=+1%2F2+%2A48%2A36+=+864+cm%5E2\" \r
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\n" ); document.write( "\n" ); document.write( "Dr. Robert J. Rapalje, Retired
\n" ); document.write( "Email: rapaljer@mathinlivingcolor.com\r
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\n" ); document.write( "\n" ); document.write( "For more FREE help with math, please see my website at www.mathinlivingcolor.com
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