document.write( "Question 342278: An open rectangular box with volume 7 m3 has a square base.
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document.write( "(a) Express the surface area of the box as a function of the length (x) of a side of the base. \n" );
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Algebra.Com's Answer #245189 by nyc_function(2741)![]() ![]() You can put this solution on YOUR website! volume = length * width * height \n" ); document.write( "square base ... let length and width = x \n" ); document.write( "x^2 * height = 7 \n" ); document.write( "height = 7 / x^2\r \n" ); document.write( "\n" ); document.write( "Surface area (with open top) = bottom + 4 sides\r \n" ); document.write( "\n" ); document.write( "Surface area = x^2 + 4 * x * height\r \n" ); document.write( "\n" ); document.write( ". . . we already know height = 7 / x^2, so substute\r \n" ); document.write( "\n" ); document.write( "Surface area = x^2 + 4x * 7 / x^2 \n" ); document.write( "Surface area = x^2 + 28 / x <======= \n" ); document.write( " \n" ); document.write( " |