document.write( "Question 87249: David drew a rectangle is 143 square mm. Derek drew a rectangle inside of David which is 35 square mm. Derek's rectangle has a three mm border between his and David's rectangle. What are the length and width of David rectangle? -Jason \n" ); document.write( "
Algebra.Com's Answer #63205 by malakumar_kos@yahoo.com(315)\"\" \"About 
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let the length &width of derek's rectangle be = l & b
\n" ); document.write( " area of the rectangle = 35 sq mm
\n" ); document.write( " length & width of David's rectangle = (l+3)&(b+3)
\n" ); document.write( " area of David's rectangle = 143 sq mm
\n" ); document.write( " (l+3)(b+3)=143 lb+3l+3b+9 =143
\n" ); document.write( " 35+3(l+b)+9 = 143
\n" ); document.write( " 3(l+b)= 143-44
\n" ); document.write( " 3(l+b)=99
\n" ); document.write( " l+b = 99/3 = 33 l = 33-b--------eq 1
\n" ); document.write( " l.b = 35 b.(33-b)=35
\n" ); document.write( " 33b-bsquare = 35\r
\n" ); document.write( "\n" ); document.write( " b(square)-33b+35=0
\n" ); document.write( " use x=(-b+-sqrt(b^2-4ac)/2.a b=33+-sqrt33^2-4.1.(-35)/2
\n" ); document.write( " b= 33+-sqrt1229/2
\n" ); document.write( " b= 33+-35.05/2
\n" ); document.write( " b = 68.05/2=34.03
\n" ); document.write( " or b=-2.05/2= -1.03\r
\n" ); document.write( "\n" ); document.write( " l=34.03 if b=-1.03 and l=-1.03 if b=34.03\r
\n" ); document.write( "\n" ); document.write( " length &width of David's rectangle = l+3=37.03 b=1.97 or vice versa \n" ); document.write( "
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