document.write( "Question 130827This question is from textbook
\n" ); document.write( ": Please help me solve this equation: the perimeter of a rectangle is 64 cm.the area is 240cm^2. what are its dimension? \n" ); document.write( "
Algebra.Com's Answer #95506 by cngriffith(27)\"\" \"About 
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P=2l+2w
\n" ); document.write( "64=2l+2w substitute 64 for P\r
\n" ); document.write( "\n" ); document.write( "A=lw substitute 240 for A
\n" ); document.write( "240=lw Solve for either l or w. I will solve for w.
\n" ); document.write( "w=240/l Divide both sides by l\r
\n" ); document.write( "\n" ); document.write( "64=2l+2(240/l) Substitution of (240/l) for w
\n" ); document.write( "64=(2l^2 +480)/l find common denominator of l and combine like terms\r
\n" ); document.write( "\n" ); document.write( "64/1=(2l^2 +480)/l Write the left side over 1 to form a proportion.
\n" ); document.write( "64=2l^2+480 Cross multiply\r
\n" ); document.write( "\n" ); document.write( "2l^2-64l+480 =0 Standard form of quadratic equation
\n" ); document.write( "2(l^-32l+240)=0 Factor out a common factor of 2
\n" ); document.write( "2(l-20)(l-12)=0 Factor the trinomial
\n" ); document.write( "l-20=0 and l-12=0 Set each variable factor equal to zero and solve each equation
\n" ); document.write( "l=20 and l-12 Let one answer be the width and one answer be the length
\n" ); document.write( "For example length = 20 and width =12
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