document.write( "Question 988688: If two opposite sides of a square are increased by 15 meters and the other sides are decreased by 7 meters, the area of the rectangle that is formed is 75 square meters. Find the area of the original square. \n" ); document.write( "
Algebra.Com's Answer #609394 by ankor@dixie-net.com(22740)\"\" \"About 
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If two opposite sides of a square are increased by 15 meters and the other sides are decreased by 7 meters, the area of the rectangle that is formed is 75 square meters.
\n" ); document.write( " Find the area of the original square.
\n" ); document.write( ":
\n" ); document.write( "let x = the side of the original square
\n" ); document.write( "then
\n" ); document.write( "(x+15) = one pair of sides
\n" ); document.write( "and
\n" ); document.write( "(x-7) = the other pair of sides
\n" ); document.write( ":
\n" ); document.write( "The area equation
\n" ); document.write( "(x+15)*(x-7) = 75
\n" ); document.write( "FOIL
\n" ); document.write( "x^2 - 7x + 15x - 105 = 75
\n" ); document.write( "x^2 + 8x - 105 - 75 = 0
\n" ); document.write( "A quadratic equation
\n" ); document.write( "x^2 + 8x - 180 = 0
\n" ); document.write( "Factor easily to
\n" ); document.write( "(x+18)(x-10) = 0
\n" ); document.write( "the positive solution
\n" ); document.write( "x = 10 m, side of the original square
\n" ); document.write( "then
\n" ); document.write( "10^2 = 100 sq/m the area of the original square \n" ); document.write( "
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