document.write( "Question 595488: The perimeter of a rectangle is 38 inches, and its area is 88 in2. Find the length of the longer and shorter side. \n" ); document.write( "
Algebra.Com's Answer #377176 by math-vortex(648)\"\" \"About 
You can put this solution on YOUR website!
Hi, there--
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\n" ); document.write( "We can solve this problem using a system of equations.
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\n" ); document.write( "[I]Define your variables.
\n" ); document.write( "L = the longer side
\n" ); document.write( "S = the shorter side\r
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\n" ); document.write( "[II] Write the system of equations.
\n" ); document.write( "We will need to use the formulas for the perimeter of a rectangle and for the area of a rectangle to write our equations.
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\n" ); document.write( "The PERIMETER is the distance around the edge of the rectangle, so an algebraic expression for the perimeter is S+L+S+L. We can simplify this to 2S+2L. Since the perimeter is 38 inches, our first equation is
\n" ); document.write( "\"2S%2B2L=38\"
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\n" ); document.write( "The AREA is the space inside the rectangle, so an algebraic expression for the area is (S)(L). Since the area is 88 square inches, our second equation is
\n" ); document.write( "\"%28S%29%28L%29=88\"
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\n" ); document.write( "[III] Solve the system of equations.
\n" ); document.write( "Let's use the substitution method. Rewrite the first equation to isolate S.
\n" ); document.write( "\"2S%2B2L=38\"
\n" ); document.write( "\"2S=38-2L\"
\n" ); document.write( "\"S=%2838-2L%29%2F2\"
\n" ); document.write( "\"S=19-L\"
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\n" ); document.write( "Substitute 19-L for S in the second equation.
\n" ); document.write( "\"%28S%29%28L%29=88\"
\n" ); document.write( "\"%2819-L%29%28L%29=88\"
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\n" ); document.write( "Simplify (you'll get a quadratic equation) and solve for L.
\n" ); document.write( "\"19L-L%5E2=88\"
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\n" ); document.write( "Rearrange the equation and set it equal to 0.
\n" ); document.write( "\"-L%5E2%2B19L-88=0\"
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\n" ); document.write( "Multiply every term by -1.
\n" ); document.write( "\"L%5E2-19L%2B88=0\"
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\n" ); document.write( "This equation factors nicely since (-11)(-8)=88 and (-11)+(-8)=-19.
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\n" ); document.write( "\"%28L-11%29%28L-8%29=0%29\"
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\n" ); document.write( "We use the zero-product property to say that either
\n" ); document.write( "\"L-11=0\"
\n" ); document.write( "or
\n" ); document.write( "\"L-8=0\"
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\n" ); document.write( "Therefore,
\n" ); document.write( "\"L=11\"
\n" ); document.write( "or
\n" ); document.write( "\"L=8\"
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\n" ); document.write( "Either the longer side is 11 inches or 8 inches. Clearly the longer side L is 11 inches since 11 is greater than 8. The shorter side S is 8 inches.
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\n" ); document.write( "[IV] Check your work checking the perimeter and area for these values!
\n" ); document.write( "Perimeter:
\n" ); document.write( "\"2L%2B2S=38\"
\n" ); document.write( "\"2%2811%29%2B2%288%29=38\"
\n" ); document.write( "\"22%2B16=38\"
\n" ); document.write( "\"38=38\"
\n" ); document.write( "Perfect!
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\n" ); document.write( "Area:
\n" ); document.write( "\"%28S%29%28L%29=88\"
\n" ); document.write( "\"%288%29%2811%29=88\"
\n" ); document.write( "\"88=88\"
\n" ); document.write( "Winner, winner, chicken dinner!
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\n" ); document.write( "That's it. Feel free to email me if you have questions about the solution.
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\n" ); document.write( "Good luck,
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\n" ); document.write( "Mrs.Figgy
\n" ); document.write( "math.in.the.vortex@gmail.com\r
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