document.write( "Question 208740: an isosceles triangle has two sides of equal length. the length os the third side is 4 ft less than twice the length of an equal side.\r
\n" ); document.write( "\n" ); document.write( "Find the length of the third side when the perimeter is 20 ft.
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Algebra.Com's Answer #157918 by checkley77(12844)\"\" \"About 
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x+x+(2x-4)=20
\n" ); document.write( "2x+2x-4=20
\n" ); document.write( "4x=20+4
\n" ); document.write( "4x=24
\n" ); document.write( "x=24/4
\n" ); document.write( "x=6 ft. is the length of the equal sides.
\n" ); document.write( "2*6-4=12-4=8 ft. is the length of the third side.
\n" ); document.write( "Proof:
\n" ); document.write( "6+6+8=20
\n" ); document.write( "20=20
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