document.write( "Question 169268: a rectangular page in a book is to have an 18 cm by 23 cm illustration in the center with equal margins on all four sides. How wide should the margins be if the page has an area of 594 square cm? \n" ); document.write( "
Algebra.Com's Answer #124811 by checkley77(12844)\"\" \"About 
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18*23=414 cm^2 is the center illustration.
\n" ); document.write( "(13+2x)(23+2x)=594
\n" ); document.write( "299+46x+26x+4x^2=594
\n" ); document.write( "4x^2+72x+299-594=0
\n" ); document.write( "4x^2+72-295=0
\n" ); document.write( "Using the quadratic equation \"x=%28-b%2B-sqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29\" we get:
\n" ); document.write( "x=(-72+-sqrt[72^2-4*4*-295])/2*4
\n" ); document.write( "x=(-72+-sqrt[5184+4720])/8
\n" ); document.write( "x=)-71+-sqrt9904)/8
\n" ); document.write( "x=(-72+-99.5188)/8
\n" ); document.write( "x=27.5188/8
\n" ); document.write( "x=3.43986 cm. ans for the margin.
\n" ); document.write( "Proof:
\n" ); document.write( "(13+2*3.43986)(23+2*4.43986)=594
\n" ); document.write( "(13+6.8797)(23+6.8797)=594
\n" ); document.write( "19.8797*29.8797=594
\n" ); document.write( "594~594\r
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